2019. Working in Chernobyl

Tags

Amphibians, Chernobyl, frogs, Research, Science, Ukraine, Wildlife

(“Trabajando en Chernobyl”, versión en español más abajo)

As soon as we talk about our research with Chernobyl wildlife a lot of people ask us how is it to work in a radioactive contaminated area. Is it dangerous? Do you leave the protection of the car? For how long can you stay in a contaminated area? Do you wear protective suits? All these questions are common for us and for all our colleagues working in Chernobyl (or Fukushima). So, before leaving on Sunday for a new research campaign in Ukraine, let’s talk a bit about how do we work inside the Chernobyl Exclusion Zone.

First, yes, we do work and stay INSIDE the Exclusion Zone for days. On a campaign like the one planned for this year, we will enter the Exclusion Zone on Monday 27^th May and stay working (and living) inside the Zone until Friday 31^st, for example. Last year we stayed inside the Exclusion Zone for even longer. Once in the Zone we stay in one of the two hostels in the old city of Chernobyl that offer accommodation mostly for tourist (yes, “catastrophe tourism” is a thing, with 70.000 people visiting Chernobyl last year). Believe it or not, we even have pretty good Wi-Fi connection in the hostel!!

Hotel Prypiat, Chernobyl.

For breakfast and dinner we move across the street to the other hostel (Prypiat Hotel). I am not going to lie, food is not the best thing about Chernobyl… If we are doing fieldwork during daytime, we just have lunch outside.

We even have a lab inside the Exclusion Zone!! We conduct all our lab work at the “facilities” that the Chornobyl Centre has in town, an old one-story house given to the Centre by the old couple that used to live there. There we have plenty of space for doing all kind of work, including a radiometer for measuring radiation dose on-site, digital scales, microscope, freezers and the big luxury of having the possibility to get liquid nitrogen!! We can keep there also our field equipment: wading boots and all kind of boxes for keeping our frogs. This place is really a gem without which we could not do our research. And all thanks to the work and dedication of our friend and collaborator Sergey Gaschak, head of the Radioecology Laboratory of the Chornobyl Centre, the most wonderful expert in Chernobyl wildlife you can ask for!!

Radiation level in the old Chernobyl city (do not mix with the larger Pripyat city, about 20 km to the Northwest) are pretty low (around 0.2 microSv/hour), same as in many big cities in Europe for example. This city was evacuated on the 27 April 1986 (14.000 inhabitants), but now is a place not only for hostels and tourists, but also for many governmental agencies and a floating population of a few thousand persons that live today in Chernobyl, working on shifts on the power plant maintenance and decontamination. You can even find a couple of general stores in the city, an ATM, and last year a new grill bar opened!!

Once in the field, we move all across the different radiation levels, from some of the most radioactive places on Earth like the “famous” Red Forest, or the Azbuchy and Hluboke lakes, to places towards the center and south of the Exclusion Zone that maintain now background radiation levels. Anyway, even in the contaminated areas, radiation level is highly variable and patchy, and just by moving a few meters radiation levels can change by an order of magnitude or more. Anyway, doing research in these areas is pretty safe. From our experience working in Chernobyl, a week without leaving the Exclusion Zone equals to around 100-150 microSv of accumulated radiation dose, whereas a flight New York-Los Angeles equals 40, a mammogram 400, or a head CT scan 2000. Not much, really.

So, most of the time we wear absolutely normal field clothes. The same clothes we would use when looking for frogs in any other place. Nothing special.

Only when working in the most contaminated areas we wear (sometimes) the classic white suits that a lot of people know. But, I must say, these are not really protective suits. They do not protect you from the radiation at all. Radiation penetrates through this fabric as it does with any other normal fabric. The aim of wearing this type of suit is that the fabric can retain small radioactive particles, so when you remove and discard the suits you don’t move these particles around, or even worst leave with them attached to your normal field clothes. But no more, no less. Another piece or equipment is the face mask, again only used in high radiation areas, and with the mission of avoiding breathing one of these hot radioactive particles that may be floating in the air. These masks are especially useful if you are removing soil for sampling (this year we will do a bit of this), since most of these hot particles are trapped in the soil, and it is not a good idea to get one inside.

Overall, yes, it is pretty safe to work in the area.

Yes, we stay inside the Exclusion Zone for days, working, eating and sleeping there, no problem.

And, no, we don’t wear these fancy suits and masks that you see on the TV documentaries about Chernobyl.

Time now for us to pack all the research material that we need for working in the Zone during a week, and to plan carefully everything we want to do in Chernobyl this year. A few more days and we will write from Chernobyl, inside the Exclusion Zone.

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2019. Trabajando en Chernobyl

En cuanto hablamos de nuestra investigación con la fauna salvaje de Chernobyl, muchas personas nos preguntan cómo es trabajar en un área contaminada con radiación. ¿Es peligroso? ¿Dejáis la protección del coche? ¿Cuánto tiempo permanecéis en un área contaminada? ¿Usáis trajes de protección? Todas estas preguntas son habituales para nosotros y para todos nuestros colegas que trabajan en Chernobyl (o Fukushima). Así que, antes de partir el domingo para una nueva campaña de investigación en Ucrania, vamos a hablar un poco sobre cómo trabajamos dentro de la Zona de Exclusión de Chernobyl.
En primer lugar, sí, trabajamos y vivimos DENTRO de la Zona de Exclusión durante días. Por ejemplo, en una campaña como la planeada para este año, entraremos en la Zona de Exclusión el lunes 27 de mayo y estaremos trabajando (y viviendo) dentro de la Zona hasta el viernes 31. El año pasado nos quedamos dentro de la Zona de Exclusión incluso más tiempo. Una vez en la Zona, nos alojamos en uno de los dos albergues en la ciudad de Chernobyl que ofrecen alojamiento principalmente para turistas (sí, el “turismo de catástrofes” está de moda, con 70.000 personas visitando Chernobyl el año pasado). Aunque parezca mentira, incluso tenemos una buena conexión Wi-Fi en el albergue.
Para el desayuno y la cena, simplemente cruzamos la calle hacia el otro albergue (Prypiat Hotel). No voy a mentir, la comida no es lo mejor de Chernobyl … Si estamos haciendo trabajo de campo durante el día, comemos fuera al lado del coche, y ya.
¡A la hora de trabajar, tenemos incluso un laboratorio dentro de la Zona de Exclusión! Llevamos a cabo todo nuestro trabajo de laboratorio en las “instalaciones” que el Centro Chornobyl tiene en la ciudad. Una antigua casa de una sola planta que la pareja que vivía allí dejó al Centro para sus actividades. Ahí tenemos mucho espacio para hacer todo tipo de trabajo, incluido un radiómetro para medir la dosis de radiación en el sitio, balanzas digitales, microscopio, congeladores y el gran lujo de tener la posibilidad de obtener nitrógeno líquido. Podemos mantener allí también nuestro equipo de campo: vadeadores y todo tipo de cajas para mantener a las ranas. Este lugar es realmente una joya sin la cual no podríamos hacer nuestra investigación. Y todo gracias al trabajo y la dedicación de nuestro amigo y colaborador Sergey Gaschak, jefe del Laboratorio de Radioecología del Centro Chornobyl, el mayor experto en la naturaleza de Chernobyl que se puede pedir.

El nivel de radiación en la antigua ciudad de Chernobyl (no confundir con la ciudad de Pripyat, mayor y a unos 20 km al noroeste) es bastante bajo (alrededor de 0.2 microSv / hora), igual que en muchas áreasde Europa, por ejemplo. Esta ciudad fue evacuada el 27 de abril de 1986 (14.000 habitantes), pero ahora es un lugar no solo con albergues y turistas, sino también la sede de muchas agencias gubernamentales y el lugar de descanso de una población flotante de unos pocos miles de personas que viven trabajando por turnos en el mantenimiento y descontaminación de la central nuclear. ¡Incluso es posible encontrar un par de tiendas en general en la ciudad, un cajero automático, y el año pasado se abrió un nuevo bar asador!
Una vez en el campo, nos movemos a través de los diferentes niveles de radiación, desde algunos de los lugares más radiactivos de la Tierra, como el “famoso” Bosque Rojo, o los lagos Azbuchy y Hluboke, o en lugares hacia el centro y al sur de la Zona de Exclusión que mantienen en la actualidad niveles de radiación basales. De todos modos, incluso en las áreas contaminadas, el nivel de radiación es muy variable e irregular, y solo con moverse unos pocos metros, los niveles de radiación pueden cambiar en un orden de magnitud o más. En resumen, trabajar en estas áreas es bastante seguro. Según nuestra experiencia en Chernobyl, una semana sin salir de la Zona de Exclusión equivale a una dosis de radiación acumulada de alrededor de 100-150 microSv, mientras que un vuelo Nueva York-Los Ángeles equivale a 40, una mamografía 400 o una tomografía computarizada de cabeza 2000.
Por ello, la mayoría de las veces usamos ropa de campo absolutamente normal. La misma ropa que usaríamos para buscar ranas en cualquier otro lugar. Nada especial.

Solo cuando trabajamos en las áreas más contaminadas usamos (a veces) los trajes blancos clásicos que mucha gente conoce. Pero, es importante decir, estos no son realmente trajes de protección, ya que no protegen en absoluto de la radiación. La radiación penetra a través de este tejido como lo hace con cualquier otro tejido normal. El objetivo de usar este tipo de traje es que la tela puede retener pequeñas partículas radiactivas, por lo que cuando te quitas estos trajes y los desechas, evitas llevarte partículas radioactivas a otro sitio, o lo que es peor que se adhieran a la ropa de campo normal. Otra pieza de equipo típica es la mascarilla, que usamos en áreas de alta radiación con la misión de evitar respirar partículas radiactivas que pueden estar flotando en el aire. Estas máscaras son especialmente útiles si está removiendo el suelo para muestrear (este año haremos este tipo de muestreo), ya que la mayoría de estas partículas están atrapadas en el suelo, y no es buena idea respirar una.

 

En resume, sí, es bastante seguro trabajar en Chernobyl.

Sí, nos quedamos dentro de la Zona de Exclusión durante días, trabajando, comiendo y durmiendo allí, sin problema.

Y, no, no usamos estos trajes y máscaras tan espectaculares que se ven en los documentales de televisión sobre Chernobyl. La mayor parte del tiempo usamos ropa normal.

 

Ahora nos toca hacer las maletas y meter todo el material de investigación que necesitamos para trabajar en la Zona durante una semana, y planear cuidadosamente todo lo que queremos hacer en Chernobyl este año. Unos días más y escribiremos desde Chernobyl, dentro de la Zona de Exclusión.

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2019. Back to Chernobyl

Tags

Amphibians, Chernobyl, frogs, Research, Science, Ukraine, Wildlife

(”Volvemos a Chernobyl”, versión en español más abajo)

It’s May again, so is time for us to get ready for a new season of field work in Chernobyl. This will be the fourth consecutive year that we will work in Ukraine trying to evaluate the situation of the wildlife living inside the Exclusion Zone. We will work once more in the Ukrainian side of the Exclusion Zone, which covers an area of about 2600 km² and was established after the nuclear accident in 1986. In this area public access and settlement are still restricted. More than 30 years have pass since the accident, and the area maintains now high biodiversity, with animals like brown bears, wolves, lynxes, or 200 birds species living there. With our work we aim to evaluate the long-term effects that living in an area contaminated with radioactivity can have on this wildlife. At the same time, this setting allows us to test for the existence of rapid adaptation patterns to new environmental conditions, which may allow organisms to cope with chronic low levels of radioactive contamination.

In previous years, we have examined the responses to ionizing radiation in the Eastern treefrog (Hyla orientalis), sampling more than 250 individuals (adult males during the breeding season), across 12 different localities. These localities ranged from places with some of the highest levels of radioactive contamination in the world, to localities outside the exclusion Zone not affected by the radioactive fallout.

This year we will change the focus of our main research activities to other amphibians and other topics. Our main idea is to take tissue samples from adult individuals of the esculentus-complex, a group of three different water frog species: the edible frog (Pelophylax esculentus), the Centro European green frog (P. lessonae) and the marsh frog (P. ridibundus). Quite probably only esculentus and lessonae will be abundant in the Zone. The idea is to compare these samples with old samples that were collected in the Zone by Leo Borkin (Russian Academy of Sciences) soon after in the nuclear accident in 1987-1990. We have these samples at our UMIB lab, thanks to the efforts of our colleagues Spartak Litvinchuk (Russian Academy of Sciences) and Glib Mazepa (University of Lausanne). Our goal is to use these sample to examine the patterns of mutation accumulation, as well as possible genomic changes across time. This system has a very interesting particularity: Pelophylax esculentus is a hybrid species formed by the mating of the two parental species P. lessonae and P. ridibundus. More interesting, this species maintains hybridogenetic reproduction, which means that during gametogenesis, individuals discard the genome of one of the parental species and produce only gametes with the genome of the other parental species, without any recombination. After mating with the original parental species (a sexual host) the full genome is restored. This allow us to have a clonal genome from a vertebrate that has been living in the radioactive contaminated area from 30 years. So, we will be able to examine the accumulation of mutations and the genomic changes in this clonal genome, which has experience no recombination during all this time. A pretty unique opportunity.

Photo: Helge Busch-Paulick, Wikipedia

Our idea is to collect breeding individuals of these species in two of the original localities inside the Exclusion Zone where frogs were sampled in 1987-1990, as well as in a locality with high radiation levels that we have visited over the last three years (Azbuchyn lake, 1km from the nuclear power plant). We will visit also one locality outside the Exclusion Zone, near Slavutych, not affected by radioactive fallout that will act as an external control.

Pablo Burraco at Azbuchyn Lake, May 2018

This time, sampling should be an easy task as the species are abundant and we only need a small piece of tissue for our analyses, either a finger or a piece of interdigital membrane. The tricky part will be to differentiate the species, which are very very similar. Let’s see…

We also have old samples from the European fire-bellied toad (Bombina bombina), so we will try to catch some individuals of this species in the same localities as the esculentus frogs to do similar genomic analyses, this time in a species with normal sexual reproduction. Fire-bellied toads are also fairly abundant across the exclusion zone, although individuals are not always easy to locate despite the loud calls.

European fire-bellied toad (Bombina bombina). Photo: Marek Szczepanek. Wikipedia.

Apart of working with these amphibians, we will not forget our main target species during the previous years, the Eastern treefrog (Hyla orientalis). With this species we want to complete some small details of our coloration analyses, mainly trying to add some additional localities (and individuals) from outside of the Exclusion Zone. We also plan to perform a small experiment to look for quick plastic changes in coloration on these frogs, that will help us to understand a bit better the nature of the differences that we observe in the field.

Another additional task linked with the treefrogs will be to conduct additional sampling of environmental microbiome on the localities in which we have collected treefrogs on previous years. For all these frogs we have sampled both gut and skin microbiome, so sampling microbiome in water, soil and sediment will also help us to understand possible differences between localities and radiation levels, and to know more about the patterns of microbiome acquisition in the species. Once in Chernobyl, and if we have time, we will like to expand this sampling to many more water bodies (many of the ones we have visited in previous years, but without finding treefrogs) in order to perform a complete study of the factors that affect the diversity and composition of environmental microbiome in water bodies of the Chernobyl Exclusion Zone.

And, even more!! Once moving around the Zone, we will like to visit some areas used by the Przewalski’s horses in order to evaluate possible sampling procedures in order to obtain good, fresh fecal samples from this species. We have in mind to start a new project on these horses in collaboration with our friend and colleague Katerina Guschanski from Uppsala University (Sweden). This would be a very first step.

Of course, as in previous years, we (Pablo Burraco and I) will work together with our friend and colleague Sergey Gaschack (Chornobyl Center), the true expert of Chernobyl nature. This time, our other great colleague Jean-Marc Bonzom (IRSN-France), that was with us last year will not join us. We will miss you Jean-Marc!!

We will fly to Ukraine already this Sunday, and work in the country until the 4th June, starting our work inside the Exclusion Zone and moving out to Slavutych at the end of our stay. Eight pretty intense days of field work ahead, always looking for the warm, sunny weather needed for the frogs to be really active.

This year, for the first time, we will fly from our new location in Spain, at the UMIB-Research Unit of Biodiversity, joint research centre between the University of Oviedo and the Spanish Research Council-CSIC. And that means, among other things, that we will not have an easy direct flight as in previous years from Stockholm. Luckily the logistics this year are fairly simply, no dry-shipper for frozen sample storage for example!!!

As we did in all the previous years, we will give detailed information about our research activities in the field and the labs in Ukraine, and about how is it to move around the Exclusion Zone and work in a radioactive contaminated area as Chernobyl. We will maintain our classical daily updates on this blog, plenty of info in our Twitter accounts (@GOrizaola, @pabloburraco, using the hashtag #ChernobylFrogs19) and also on Instagram (@gorizaola). Hopefully, this year we will work more in the field during daylight, so there may be chances for recording some videos in the Zone. Keep an eye!!

Please, if you have any questions, ask us by any of these media. I hope you like it!!

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2019. Volvemos a Chernobyl

 

Es mayo de nuevo y eso significa que llega para nosotros el tiempo de una nueva temporada de trabajo de campo en Chernobyl. Este será el cuarto año consecutivo en el que trabajaremos en Ucrania para evaluar la situación de la fauna salvaje que vive dentro de la Zona de Exclusión. Trabajaremos una vez más en el lado ucraniano de la Zona de Exclusión, que cubre un área de aproximadamente 2600 km² y que se estableció después del accidente nuclear en 1986. En esta área, el acceso público y el asentamiento aún están restringidos. Ahora, más de 30 años después del accidente el área mantiene una alta biodiversidad, estando ocupada por animales como osos pardos, lobos, linces o 200 especies de aves. Con nuestro trabajo, intentamos evaluar los efectos a largo plazo que la exposición crónica radioactividad puede tener sobre la fauna salvaje de la Zona. Al mismo tiempo, nuestro trabajo nos permite examinar si pudiesen existir patrones de adaptación rápidos a las nuevas condiciones ambientales que podrían permitir a los organismos hacer frente a esos niveles crónicos de bajo contaminación radiactiva a los que están expuestos en algunos lugares de la Zona de Exclusión.

En años anteriores, hemos trabajado examinando las respuestas frente a la radiación ionizante en la Ranita de San Antonio oriental (Hyla orientalis), tomando muestras de más de 250 individuos (machos adultos durante la temporada de reproducción), en 12 localidades diferentes. Estas localidades van desde lugares con algunos de los niveles más altos de contaminación radiactiva en el mundo, hasta localidades fuera de la Zona de exclusión no afectadas por la lluvia radioactiva.

Este año cambiaremos el enfoque de nuestras principales actividades de investigación a otros anfibios y otros temas. Nuestra idea principal es tomar muestras de tejido de individuos adultos del complejo esculentus, un grupo de tres especies diferentes de ranas acuáticas: la rana comestible (Pelophylax esculentus), la rana verde centroeuropea (P. lessonae) y la rana europea común (P. ridibundus). Probablemente, solo esculentus y lessonae serán abundantes en la Zona. La idea es comparar estas muestras con muestras antiguas que fueron recogidas en la Zona por Leo Borkin (Academia de Ciencias de Rusia) poco después en el accidente nuclear de 1987-1990. Tenemos estas muestras en nuestro laboratorio de la UMIB, gracias a los esfuerzos de nuestros colegas Spartak Litvinchuk (Academia de Ciencias de Rusia) y Glib Mazepa (Universidad de Lausana). Nuestro objetivo es utilizar estas muestras para examinar los patrones de acumulación de mutaciones, así como los posibles cambios genómicos a lo largo del tiempo. Este sistema tiene una particularidad muy interesante: Pelophylax esculentus es una especie híbrida formada por el apareamiento de las dos especies parentales, P. lessonae y P. ridibundus. Más interesante aún, esta especie mantiene una reproducción hibridogenética, lo que significa que durante la gametogénesis, los individuos descartan el genoma de una de las especies parentales y producen solo gametos con el genoma de las otras especies parentales, sin ninguna recombinación. Después de aparearse con la especie original parental (que actúa como huésped sexual) se restaura el genoma completo. Esto nos permite tener un genoma clónico de un vertebrado que ha estado viviendo en el área contaminada desde hace unos 30 años. De esta manera, podremos examinar la acumulación de mutaciones y los cambios genómicos en este genoma clónico, que no ha experimentado recombinación durante todo este tiempo. Una oportunidad única.

Nuestra idea es recolectar individuos reproductores de estas especies en dos de las localidades originales dentro de la Zona de Exclusión donde se tomaron muestras en 1987-1990, así como en una localidad con altos niveles de radiación que hemos visitado en los últimos tres años (Azbuchyn lake, a 1km de la central nuclear). También visitaremos una localidad fuera de la Zona de Exclusión, cerca de Slavutych, que no se vio afectada por el accidente nuclear y que actuará como control externo.

Esta vez, el muestreo debería ser una tarea fácil ya que estas ranas son abundantes en la Zona y sólo necesitamos un pequeño trozo de tejido para nuestros análisis, ya sea un dedo o un trozo de membrana interdigital. La parte difícil será diferenciar las especies, que son muy, muy similares…

También tenemos muestras antiguas de sapo de vientre de fuego (Bombina bombina), por lo que también intentaremos capturar algunos individuos de esta especie en las mismas localidades que las ranas anteriores para realizar análisis genómicos similares, esta vez en una especie con reproducción sexual normal. Los Bombina son también bastante abundantes en la zona de exclusión, aunque los individuos no siempre son fáciles de localizar a pesar de las fuertes cantos reproductores de los machos.

Además de trabajar con estos anfibios, no olvidaremos a la especie que ha constituido nuestro principal objetivo de estudio durante los años anteriores, la Ranita de San Antonio oriental (Hyla orientalis). Con esta especie queremos completar algunos pequeños detalles de nuestros análisis de coloración, principalmente tratando de agregar algunas localidades adicionales de fuera de la Zona de Exclusión. También planeamos realizar un pequeño experimento para buscar cambios plásticos rápidos en la coloración de estas ranas, que nos ayudarán a comprender un poco mejor la naturaleza de las diferencias que observamos en el campo.

Otra tarea adicional vinculada con las Hyla será realizar un muestreo del microbioma ambiental en las localidades en las que hemos recolectado individuos en años anteriores. Para todas estas ranas, hemos muestreado microbioma intestinal y de piel, por lo que el muestreo de microbioma en agua, suelo y sedimento nos ayudará a comprender mejor las posibles diferencias entre localidades y niveles de radiación, y a conocer más sobre los patrones de adquisición de microbioma en la especie. Una vez en Chernobyl, y si tenemos tiempo, nos gustaría ampliar este muestreo a más zonas acuáticas (muchas de ellas ya visitadas en años anteriores, pero sin capturar ranas allí). Esto nos serviría para realizar un estudio completo de los factores que afectan la diversidad y la composición del microbioma ambiental en las zonas acuáticas de la Zona de Exclusión de Chernobyl.

Y, aún más!! Una vez en la Zona, nos gustaría visitar algunas áreas utilizadas por los caballos de Przewalski para evaluar posibles procedimientos de muestreo de muestras fecales frescas en esta especie. Tenemos en mente comenzar un nuevo proyecto sobre estos caballos en colaboración con nuestra amiga y colega Katerina Guschanski de la Universidad de Uppsala (Suecia), por lo que establecer un buen protocolo de recogida de muestras sería un gran primer paso.

Por supuesto, como en años anteriores, trabajaremos (Pablo Burraco y yo) junto con nuestro amigo y colega Sergey Gaschack (Centro Chornobyl), el gran experto de la naturaleza de Chernobyl. Esta vez, nuestro otro gran colega, Jean-Marc Bonzom (IRSN-Francia), que estuvo con nosotros el año pasado, no se podrá unir a nosotros. Te echaremos de menos Jean-Marc!!

Nuestra campaña de trabajo empieza este mismo domingo en le que volaremos a Ucrania, trabajando en el país hasta el 4 de junio. Comenzaremos nuestro trabajo en la Zona de Exclusión, para después movernos hacia Slavutych, y visitar zonas no afectadas por el accidente nuclear. Tenemos por delante ocho días de trabajo de campo intenso, siempre con un ojo en el parte meteorológico en busca de calor y buen tiempo, que son las condiciones ambientales ideales para que estos anfibios estén activos.

Este año, por primera vez, volaremos desde nuestra nueva ubicación en España, en la UMIB-Unidad Mixta de Investigación de Biodiversidad, centro de investigación conjunto entre la Universidad de Oviedo y el Consejo Superior de Investigaciones Científicas-CSIC. Y eso significa, entre otras cosas, que no tendremos un vuelo directo fácil como en años anteriores desde Estocolmo. Afortunadamente, la logística de este año es más sencilla que en años anteriores, por ejemplo no necesitamos nitrógeno líquido ni transportar ese contenedor (dry shipper) que tantos problemas nos ha dado en otros años!!

Como hemos hecho en todos los años anteriores, intentaremos dar información detallada sobre nuestras actividades de investigación en el campo y los laboratorios, y sobre cómo es moverse y trabajar dentro de la Zona de Exclusión de Chernobyl. Mantendremos otro año más nuestras actualizaciones diarias clásicas en este blog, mucha más información en nuestras cuentas de Twitter (@GOrizaola, @pabloburraco, usando el hashtag #ChernobylFrogs19) y también en Instagram (@gorizaola). Si todo va bien, este año trabajaremos más en el campo durante el día, por lo que deberíamos tener posibilidades de grabar algunos videos en la Zona. A ver si hay suerte!!

Y, si alguien tiene alguna pregunta, por favor que no dude en hacerla por cualquiera de estos medios!!

2018 Day 13. Back home

Tags

Amphibians, Biology, Chernobyl, Ecology, Fieldwork, frogs, Radioecology, Research, Science, Ukraine, Wildlife, Zoology

25 May 2018

A bit late this update of our last day in the #ChernobylFrogs18 campaign, but that’s what happens when you arrive home from Ukraine to find a general failure of internet in your neighborhood that will last for a week…

This was the final day of our 2018 campaign in Ukraine investigating the effects of the chronic exposure to the radiation released by the Chernobyl accident on the amphibians.

It was time to go for the last time to our lab at Slavutych, check the dry shipper levels once more, and put everything in the van that will transport us to Kiev airport. This time, we travelled with our expert in bureaucracy from the Chornobyl Centre, to help us with the export and flight permits. This time the trip was not as shaky as the previous one, a much better road that in about two hours leave us to the airport.

Once there, the first stop was with the airport veterinary, to check that all our samples were in order, and we had all the permits needed to fly with them. It took about one hour of waiting but there was no problem at the end. Next stop was at the oversized luggage for Jean-Marc, the first to fly and the one carrying the dry shipper. Again, all fine, it as last year… However, this lack of problems did not last until the end. Soon by realize that Jean-Marc flight to Frankfurt was delayed. So much delayed that we star fearing about his possibilities to make the connection to Marseille (only 1:05h between the two flights). At the end, the flight took off with about one hour of delay. To me, it was clear that it was not possible for him (even less for the oversized shipper) to make the connection. And, even worse, that flight was the last one to Marseille that day, with a strike of traffic controllers organized for the following day. Things did not look good. If something happens to the shipper, all the work of these days could be at risk, most of our samples lost.

With this on mind, it was time for Pablo and me to get our flight back to Sweden. We arrived even before scheduled, just to know that somehow (I still don’t understand how…) Jean-Marc and the shipper were in Marseille. No problems, all good. All happy!!!

Now, it is time for us to organize this material, all the data and samples collected during this intensive campaign. Soon, Jean-Marc will fly here with part of the samples that we will analize here. Others will stay in France for other different analyses. Time also to rest a bit.

Next, and final post of the campaign will be a summary of all our work during these weeks in Ukraine, a great time spent with our amazing Ukrainian colleagues, and with a very successful result.

2018 Day 12. Packing time

Tags

Amphibians, Biology, Chernobyl, Ecology, Fieldwork, frogs, Radioecology, Research, Science, Ukraine, Wildlife, Zoology

24 May 2018

Our last day of work in Ukraine for this season. After almost two weeks working here, it was time for us to finish sampling the last frogs and pack all our equipment. We are ready now for going back to Kiev and to our research centers in Sweden and France. All the samples collected here. Together with the ones collected in 2016 and 2017, they will keep us busy for a very long time.

During the morning, we worked in the lab as usual, sampling the 9 frogs collected the previous night in a clean locality close to Slavutych. We used one of these frogs for a full sampling of tissues with the idea of joining the two from last day as references for our genomic and transcriptomic studies. We also run our last blood samples on our analyzer, for a total of about 100 samples during the campaign, including some in duplicate to test the reliability of the machine. This has been something new for this year, and something that has worked incredibly well!!

Everything was finished for lunchtime. All frogs sampled, all material clean, all vials stored in our dry shipper full of liquid nitrogen for now. Back from lunch, it was time to carefully pack all our sampling material, the camera, iSTAT, boxes of non freeze samples (sperm, bone for skeletochronology) and blood smears for immunological studies. Some of these things will go with Pablo and me back to Uppsala, and some with Jean-Marc to France, together with the shipper. In a few days, Jean-Marc will travel with quite a few of these frozen samples to Uppsala, so we can start to work with them quickly.

Everything was ready pretty soon. It was also time to announce the winner of our “Chernobyl Frogs 2018: The Game”. It has been funny, especially during the last days, to see how close or far people was for the real number of frogs. Many, including ourselves, were too optimistic suggesting numbers well over 150 frogs… At the end, the total number of frogs collected in the trip was 109. And the winner, Claire Keeley, predicting 107, really, really close!! Also very close were Martina Ferraguti (104) and Rafael Gutierrez (103), with just a bit too few, and Jesús Orizaola (117) and Katja Guschanski (117), with just a bit too many. Well done everyone!! And thanks for participating!! The photo will be going to Claire very soon!!

Time to leave the Slavutych lab for the last time. Tomorrow we will pass by here to put all this material in our van, and drive to Kiev-Boryspol airport. Jean-Marc will be the first one departing at 5:30 PM, then it will be time for Pablo and me to fly to Sweden at 8:30 PM. The idea is to leave Slavutych with plenty of time, we have ahead bumpy roads, possible traffic jams, airport bureaucracy for exporting the samples, and we need to be ready for the usual complications with our dry shipper (hopefully not as many as last year). Luckily, we will have people from the Chornobyl Center helping us with the paperwork. Fingers crossed for good trips for us, and our samples!! One more day here, the last of our work in Ukraine. Time to get back home with the family, and back to the working routines. Tomorrow, last daily dispatch from the field!!

2018 Day 11. Last night in the field

Tags

Amphibians, Biology, Chernobyl, Ecology, Fieldwork, frogs, Radioecology, Research, Science, Ukraine, Wildlife, Zoology

23 May 2018

That’s all. Last night was our last time in the ponds collecting frogs for our #ChernobylFrogs18 campaign. And was, again, a successful night. Every single night, except the first one, we have managed to collect frogs. That’s quite remarkable. And although we have caught not as many frogs as we wanted (as always), we can say now that the trip has been extremely successful!!

We started the day in the lab, sampling our frogs from last night, the first outside the Chernobyl Exclusion Zone. These ten frogs are really important as they will represent our reference for individuals living in areas not affected by radiation. They are our baseline to which to compare the individuals from high, medium and low contamination areas that we collected the previous days, and the previous years since the start of the project in 2016.

It took us quite some time to process these frogs, in particular the last two ones for which we took additional samples to be used as references in our genomic and transcriptomic studies. With these frogs we have sampled already 100 individuals, about 1400 criovials, and 88 successful blood profiles with the iSTAT analyzer. This will keep us busy from quite some time, no doubt…

On the afternoon, we moved to an area of flooded meadows near Slavutych trying to catch the last frog from the campaign. This time we did not use our trusty Chinese car (“the tank”) but a legend of Chernobyl research, a car that has accumulated more than 800.000 kilometers (“the crocodile”, as Kat Raines named). That’s more than going to the moon and back!!!

Once again, we arrived with plenty of time to the field, a really nice place full of flowers and birds, and with plenty of fire-bellied toads calling in the distance. It was also time to be surrounded one more night by masses and masses of mosquitoes. But it allows us to see the area and plenty of beautiful iris!!

We walked and waited, and walked and waited… Until, with the last light of the day disappearing, we heard the first treefrog call. Not too may it seemed, not too active, but probably enough to use it as our final locality and final frogs of the year. We moved into the ponds, and indeed it was clear that we will need to move up and down, here and there, if we wanted to have some frogs… And that we did. It took us almost two hours to catch some frogs, until all calling activity stopped. That’s it, these are the last frogs of the trip.

Same as in the previous night, these frogs live in a clean area, a place that was not affected by the radioactive fallout in 1986, and will be part of our baseline, our reference to compare them with the Chernobyl frogs. Really precious frogs indeed!!!

By the way, for the people participating in our “Chernobyl Frogs Game”, how many frogs did we caught last night? What is it the grand total? Well, we will just keep a bit the suspense, until the next post, ok?

The plan for today is to sample these frogs during the day here in Slavutych, pack all our field and lab stuff, and get ready to travel back to Kiev on Friday morning for our flights back home. People here start to be really tired of the hard work and the constant fiel-lab routine every day. Time to get back and get some rest.

Have a nice day!!

2018 Day 9. Moving day

Tags

Amphibians, Biology, Chernobyl, Ecology, Fieldwork, frogs, Radioecology, Research, Science, Ukraine, Wildlife, Zoology

21 May 2018

Today it was a transition day for us here in the #ChernobylFrogs18 research project. After expending a full week inside the Chernobyl Exclusion Zone collecting treefrogs for our studies, it was time to move out and try catching frogs in areas never affected by the radioactive fallout after de 1986 accident in the Chernobyl Power Plant. So, we move to the east, to the city of Slavutych.

As usual, we started the day working in the lab obtaining samples from the 11 frogs collected the previous night. These frogs put our total for the trip, so far, in 90 frogs collected in six different localities inside the Exclusion Zone, two from high radiation area, one from medium, and three from low radiation levels. This is a great number, especially considering that the season this year is well advanced due to the intense warm in early spring, and that the weather was a bit colder than ideal. At least weather wasn’t like last year with temperatures barely over zero!!

Our job in the lab was very quick, the more days they pass the faster we go. We tried something new to communicate what we do here and used Twitter combining the hashtags #ChernobylFrogs18 and #liveScience to transmit live our work in the lab, resulting in 17 tweets. It was a fun experience, let’s see if it is possible to repeat something similar today from the field…

As usual, Sergey was in charge of the radiometer, measuring the radioactive content of our frogs, whereas Pablo, Jean-Marc and I, got the physiological and genetic samples from all the frogs.

We finished for lunch time, and quickly packed all our equipment again, from the tubes and scissors, to the cameras and the portable lamps. Everything needed for our work. This included also our dry shipper, refilled with more liquid nitrogen and very, very, full of samples. After waiting a while for our van, we moved to the main checkpoint of the Exclusion Zone. Our car was checked for radioactive contamination, our luggage was checked for radioactive contamination, and we were also checked for radioactive contamination. Our paperwork was in order, all permits stamped and approved. All clear, all fine. We passed the detection archs for radioactive contamination and out!!

Our drive from Chernobyl to Slavutych was a long, jumpy, drive. This drive usually takes 45 minutes by the direct road crossing Belarus, but due to bureaucratic issues it was impossible for us and our equipment and samples. We had to go all the way around to avoid crossing Belarus. At that means a 4 hour drive, first South to the outskirts of Kiev, and back North towards Slavutych. This was the bumpiest drive we have ever had, for kilometers and kilometers we were jumping like monkeys inside the van. It was even difficult to hear each other in the middle of the noise. Not the most confortable drive, really not. On Friday, we will do part of this drive again in our way to the airport… Anyway, on arrival it was Sergey waiting for us to show us our apartment for these days in Slavutych, and we finally drove through the city to a local restaurant in which we had an amazing dinner!!

Even better, after a full week of movement restrictions inside the Chernobyl Exclusion Zone, we were able to move freely through the city in our way back to the apartment!! Back to the free world!!

Our plan for today is going to explore areas near Slavutych and Chernihiv, looking for potential good places for frog sampling during the night. Weather forecast, again, is not super good, although it should improve during the day and the rest of our time here. It will be challenging trying to find a good place for treefrogs without much previous knowledge, but the area looks good and the search will be exciting, no doubt. Let’s see…

2018 Day 8. Easy frogs

Tags

Amphibians, Biology, Chernobyl, Ecology, Fieldwork, frogs, Radioecology, Research, Science, Ukraine, Wildlife, Zoology

20 May 2018

An unusual night, very unusual night.. Weather forecast was bad, cold and probably rainy night, with no big hopes for catching more frogs in our last night inside Chernobyl Exclusion Zone. But… we ended up catching 11 new frogs in just twenty inmutes, in a locality visited last year, with plenty of time for photos, enjoy the landscape and taking it easy…

During the day, we worked pretty fast at the lab, finishing the last six frogs that remained from the previous day, and collecting all the samples from the seven individuals collected in clean area the previous night. Still, this take us the entire morning, with behavioral and coloration tests and the fourteen vials of different kind collected for each individual.

All blood analyses worked well, and we even had the possibility of running a few in duplicate to test the repetibility of the measures obtained with the iSTAT. Anyway, we finished just in time for lunch, once again prepared by Zenja, the best food (by far) we have had in Chernobyl. No more sampling to day, good food and a (finally) free afternoon ahead were the perfect excuse for opening the bottle of Alsatian white wine brought here by Jean-Marc. Excellent!!

We enjoyed a relaxed afternoon taking advantage of our WiFi connection at the hotel for keeping up with the family, the work outside here, and the world. Also for talking about our #ChernobylFrogs18 work in our Twitter accounts @pabloburraco, @bioecologie and @GOrizaola. Check there for more photos and comments!!

We also had time to properly store our data in our web repository, something essential when doing fieldwork, for a proper accountability of the work, and to avoid loosing data for unwanted reasons. So, we uploaded all the photos we have taken to our data during these days. Safety is an important part of Science, and not just the personal one.

After the usual early dinner, it was time for more fieldwork. Our last night inside Chernobyl Exclusion Zone, our last chance to add more frogs from the Zone for our study. Weather was supposed to be windy and cold with some possibilities of rain, not the best combination for catching frogs. Soon we realized that, although cold, the afternoon was not that bad, actually pretty nice.

We visited first a marsh area in the south side of the Exclusion Zone, a new locality for us, just to see that it was completely dry after the unusual warm weather of the spring. Anyway, light was perfect and we had plenty of time for taking photos, even Sergey took the camera out!!!

With that light and time before sunset, we had also the chance of taking a group photo (thanks again to Jean-Marc, our “official photographer “). Below, left to right, Jean-Marc, Zenja, me, Sergey and Pablo, the #ChernobylFrogs18 dream team!!

After this, and the removal of another tree from the middle of the road with a chainsaw, and the car stacked for a minute into the remains of trees, we arrived at a new location, the same location Sergey, Zenja, Pablo and I visited the first night last year. It was cold already, but as soon as we opened the car doors treefrog calls can be heard everywhere. No doubt that we were going to catch frogs, even more since we just needed a few. The idea was catching 8, but I quickly suggested 10 🙂 At the end, we managed to catch 11 new individuals in just twenty minutes, easy. Our total for the trip is now on 90, pretty, pretty good. Jean-Marc even took his camera to the field, so we have now these photos we never have, photos of fieldwork action. Pretty cool!!! In summary, a great, easy, really enjoyable night!!!

The plan for today is going quick to the lab, try to work as fast as possible sampling these 11 frogs, pack all our field and lab stuff, and try to be ready around lunchtime to leave the Exclusion Zone. Our goal now is to move outside the Zone, to Slavutych, a city created after the accident of the nuclear power plant to serve as home to people working in different jobs in the Zone. It’s a 45 minutes drive through Belarus (if no incidences at the border pass), but we can’t go that way due to the bureaucratic complexities of being three foreigners with a lot of weird scientific stuff (dry shipper, blood analyzer, samples, some chemicals…). Too complicated. So, it will take us four hours (!!!), driving back to Kiev and up again. Once in Slavutych, we will have three more nights for collecting frogs in areas never affected by radioactive contamination, essential to be used as references in many of our studies, particularly the genomic ones. If the weather is not too bad (cold forecasted) and we don’t arrive too late, we may try to go to the field tonight near Slavutych, if not we will have Tuesday and Wednesday ights for this. Let’s see how it goes in this new area!!

Working in clean areas only add the usual 3 microSv to our accumulated dose, for a total of 46 for the entire trip.

2018 Day 7. Frogs in the labyrinth

Tags

Amphibians, Biology, Chernobyl, Ecology, Fieldwork, frogs, Radioecology, Research, Science, Ukraine, Wildlife, Zoology

19 May 2017

Today was a completely non-stop day. We spent 10 full hours working in the lab, sampling the frogs collected the previous night, just to jump into the car and go to the field for more. At the end, we collected seven more frogs from a completely new locality in the middle of the Exclusion Zone, a total labyrinth of trees and shrubs in which catching frogs was a bit of an odyssey.

We started the day still with the happy face of the 30 frogs collected the night before. This number, collected in two different localities (one new) is really important for having good sample size for some of the new traits that we are evaluating this year. Anyway, we knew that doing a full sampling of all these frogs will take a lot, a lot, of time…

As in previous days, we collected information and samples for about 30 different traits for each individual, from photos to evaluate coloration and swabs of the skin microbiome, to blood biochemical profile, and all kind of tissues for physiological and genomic analyses. A lot of work that takes more than 20 minutes per individual to Pablo, Jean-Marc and me. On top of that Sergey and Zenja are measuring individual dose rate with the radiometer. An amazingly complex and complete sampling!!

Even with all the quick work, we were unable to process the last six individuals before dinner time. Weather didn’t look too good during the day, big clouds, rain and a substantial drop in temperatures, far from the preferred conditions for catching treefrogs. We discussed if going to the field or not, and at the end we decided that we must go, to no surprise for our Ukrainian colleagues 🙂 This was probably the last night we had to catch more frogs inside the Exclusion Zone before moving out for more frog collection. So, there were no alternatives really.

We decided to move to an area around the center of the Exclusion Zone that we had not visited before. This area has really low levels of radioactive contamination, a good option for us after sampling already in three localities with medium and high levels. First places that we checked during the night look really good and with good activity of fire-bellied toads, but not a sign of treefrogs. After some more driving we arrived at a locality a bit in the middle of the forest, with treefrogs calling on the distance. There were not too many, but it was our best option.

Soon after entering into the pond it was clear that the place was difficult for catching frogs. A bog area full of shrubs and dead trees in which it was difficult to move due to all the branches closing the way. It was also a little nightmare of mosquitoes… Treefrogs were calling from the middle of the trees just to make things a bit more difficult. After a good while, we managed to catch seven frogs (5 Sergey!!, 2 me) at that was all. Not much, but this is a locality in which we had never worked before, so these samples are particularly important for our study. This is especially true for our population genetics studies, since this locality sits in the middle of the Exclusion Zone, covering a gap in our sampling map. Few, but important.

The night was cold and with no more frog activity, so we moved back to the cars and into Chernobyl city.

The plan for today is finish with the sampling of the six remaining from the previous night and fully process these seven individuals. The right amount of work to be busy but not that crazy busy as last day. On Monday, we will move out of the Exclusion Zone, towards Slavutych (the administrative center of the Radioecology Laboratory) for trying to catch frogs in never-contaminated areas. So, it’s not clear if we are going to be in the field during the night or not, since we wouldn’t have much time to process any frogs tomorrow morning. Weather forecast doesn’t look very good either. So, probably these frogs will be the last from the Zone for now, a total of 79 so far for the trip.

Being in clean areas means that we accumulate the standard 3 microSv today, for a total of 43 microSv for the trip. During the night we saw red deer, roe deer, white-breasted hedgehog and even a tortoise.

More tomorrow. Thanks for following our work in the Chernobyl Exclusion Zone, our attempt to tell scientific activities “live”.

2018 Day 6. Treefrog radioactive paradise

Tags

Amphibians, Biology, Chernobyl, Ecology, Fieldwork, frogs, Radioecology, Research, Science, Ukraine, Wildlife, Zoology

18 May 2018

30. We collected 30 treefrogs on a single night!!

Once again the visit to the long ditch that runs parallel to the east side of Prypiat river on the nort if the Exclusion Zone give us the best results. This area, in which we have sampled in five different localities over the three years of our “Chernobyl frogs” project is definitely a paradise for amphibians, despite being an area with medium and high radiation levels.

We started our daily routines in the lab, sampling the thirteen frogs collected the previous night near Chernobyl city in an area of low radiation levels. Work on the lab was more or less as usual. There are never two equal days on a field lab, and there are always small incidences that need to be solved on the spot. Anyway, work on the lab was good, and there were not too many frogs to deal with.

Sergey even managed to pass all the frogs through the radiometer, so we have now good measurements of radioactive dose rate from all our frogs, including these from clean areas. Actually, it tourned out that not all these frogs were completely clean from radiation, and some showed low levels of contamination. Even more interesting.

Thanks to our acquired abilities (mostly, the amazing Jean-Marc’s technique of extracting blood!!) we were also able to run successful blood analyses for 12 out of the 13 frogs. These are amazing results that will tell us a lot of details about the physiological state of all these frogs. Results so far, after a quick view, are pretty consistent, showing variability on the diverse parameters we measure, but always between reasonable limits. We need to keep on adding more data here!!

By mid afternoon all the samples were collected. With the work, cryovials have started to accumulate in our dry shipper, and we even needed to add more liquid nitrogen there. This is one of the “luxuries ” of working here, with the International Radioecology Laboratory people, we have access (although not easy access) to good amounts of liquid nitrogen in the field, essential for storing all our samples for conducting physiological and genetic analyses.

Weather forecast was not too good for the night, with chance of rain, and temperatures going down. Anyway, after our early dinner we were ready to go to the field, with the idea of visiting different locations along the east bank of the Prypiat river, in the north of the Exclusion Zone. We have worked in this area since 2016, always with success. We started our journey to this area with good vibes, although the way was not as easy as expected, and we even need to take out a rather large tree from the middle of the path!!!

Once on location, we split our group in two teams, as in some previous days. We arrived to our first locality after a drive across the middle of nowhere, going around trees and up and down bumpy fields. This route, by the way, it would be impossible to do without the navigation skills of our Ukrainian colleagues that identified and marked this track for us many months ago. Thanks!!

After stopping, Evgeny (Žénja), Pablo and I moved to the first pond, and Sergey and Jean-Marc went back to sample on different localities. Our locality was located in rather high levels of radioactive contamination, with peaks around 20-30 microSv/hour (normal, background levels are around 0.1-0.3 microSv/hour). Soon after arriving we heard our first treefrog!! After twenty minutes more treefrogs were calling in the distance and we moved in. The area was easy for orientation, with few water channels going in circle. Water level was a bit higher than ideal, although enough (just barely enough) for working and crossing from side to side of the channels. The first frogs I caught were totally on the limit, captured with one hand while the other was putting the chest waders up in order to avoid water entry. Five centimeters deeper and they would have been out of reach…

Some frogs were loyal to their name and often calling from tree branches, a meter high from the water. Not always was easy to spot them there, and twice I had to use my left hand to catch them from a crisscross of branches (both times successfully!!). Through the phone we knew that our colleagues were not successful on their first locality, but managed to collect 16 frogs on a second place in which we have worked since 2016, on mid radiation levels.

At the end, we were also able to catch 14 frogs in our place, for an amazing total of 30 for the night, including a completely new locality. That’s fantastic!!! It was a particularly good night for Sergey and me, both with 11 frogs captured 🙂 These 30 frogs will definitely give us lot of things to do in the lab…

So, the plan for today is an intensive, super intensive, session of work in the lab with these frogs (let’s see if we can finish them before the night). If weather is good (forecast of rain for the entire day), we will try to capture more frogs in mid-high contamination areas close to Belarus. Anyway, long day ahead f work, sweet!!

Working on high contamination area resulted in a daily dose rate of 15 microSv, for a total of 40 for our trip. On the way today, we saw mousse, red deer, wild boar, white-tailed eagle…

2018 Day 5. Lucky thirteen

Tags

Amphibians, Biology, Chernobyl, Ecology, Fieldwork, frogs, Radioecology, Research, Science, Ukraine, Wildlife, Zoology

17 May 2018

Frog activity is still rather low in the Zone, but last night we managed to catch 13 frogs in a completely new locality for us, our locality 13 for the project!! Activity in the lab run smoothly too. We only need now some good weather and a night of good frog activity to move forward.

The day started as usual with lab work, sampling the last frogs from our first high contamination locality that we didn’t had the time to finish the previous day, and the additional six collected in two localities the previous night. Our work in the lab is pretty well organized by now, and by lunchtime we were able to finish with all the frogs. We managed to run samples in the iSTAT blood analyzer for all the frogs but one. The technique by now is fully under control!! This will give us a really good indication of the physiological situation of our study frogs in the Zone.

We even had the time for taking some good photos of our frogs (wait for Jean-Marc great photos!!). These are the kind of photos we will keep on using again and again in our work, when given talks, publishing papers or having any communication activity. So, in a way, they are also important for the project!!

Talking about photos, Pablo continues with our colorimetric studies trying to assess the variation of frog coloration and if this changes with contamination level. So far, no many dark frogs this year, just a few.

Due to some bureaucratic limitations we didn’t had the chance of going too far during the night, so we had to work in low contamination areas during the night. Sergey drove us to a marsh area quite close to Chernobyl city we had not visited before.

We arrived to this place with plenty of time before dusk, just to listen to many water frogs and fire-bellied toads in the distance. No sign of our treefrogs, but we now that at this time we need to way until it gets dark for these frogs to start calling. So, we wait and wait. During this time, Sergey was able to imitate the call of a tawny owl (Strix aluco) good enough as to attract it at a very close range. That was fun.. At the same time, far away, we heard the first treefrog calling. Time to put the chest waders on and move through the reeds to find the place where they were calling.

Calling activity was low. Once there it was possible to listen to 4-5 males, good but not super good. At the end, after quite a lot of patience, the five of us managed to catch thirteen frogs in about an hour of moving back and forth through the pond. This is great. A completely new locality for the project, just in the middle of all our previous localities and with enough frogs as to do many good tests. Being a low contamination site is also quite good, since most of the frogs we had until now this season were from a highly contaminated place. Sweet!!

After this, we move to the same location in which we capture four frogs the previous night, but there was no additional activity there. Not even in another place in which we also collected frogs in 2016. The night started to be cold, so we decided to get back and try more luck in the next night.

So, the plan for today is lab work during the morning with these thirteen frogs, and try to go to some mid contaminated localities on the east bank of Prypiat river during the night. We have worked there the last two years and we know that this is good treefrog area. So, let’s see how it goes, and if the weather stays good (some rain forecasted and a bit colder than we wanted…).

Working in low contamination areas, we only accumulated 3 more microSv to our total dose, for a total of 25 microSv during the trip. During the night, we also saw Przewalski horses, a nice group on our last location, rumbling in the middle of the foggy night.