Caspian seal project
The Caspian seal project began in 1997, when Sue Wilson, under the auspices of the new World Bank Caspian Environment Programme, went to Azerbaijan to investigate - together with a local scientists, Dr Tariel Eybatov - a large-scale seal mortality reported by the environment manager of the international oil consortium AIOC (now BP) operating an oil field offshore from Baku. Tissue samples taken from a few dead seals revealed two significant findings: the presence of very high levels of DDT residues in adult males and the occurrence of a new strain of canine distemper virus.
Following this, Sue Wilson and a World Bank colleague, Amy Evans, developed a proposal for a Caspian-wide study of toxic contaminants in the sea-bed sediments, bony fish, sturgeon and seals. The project was to investigate all causes of seal mortality. The 'Ecotox' project was funded by the World Bank through a donation from the Japanese Government Trust fund. At the same time, concern was growing over the invasion of the Caspian Sea by a comb jelly Mnemiopsis leidyi - carried into the Caspian by shipping in ballast water. This jelly is a voracious predator of zooplankton, and a collapse of plankton-dependent fish populations was feared, which would in turn impact on the seal population. Fortunately the impact, though serious, has not been as bad as originally feared.
The start of the Ecotox project coincided with another mass seal mortality - this time widely reported in the media - in spring 2000. The investigation was coordinated by Sue Wilson, but this time included local scientists from Kazakhstan (Dr Aidyn Kydyrmanov), Iran (Dr Hormoz Asadi) and Turkmenistan (Dr Pavel Erokhin) as well as Dr Eybatov from Azerbaijan, and marine mammal pathology experts from the Zoological Society of London, Dept of Vet. pathology at Stormont, Belfast, Institute of Animal Health at Pirbright and the Institute of Virology of Erasmus University in the Netherlands. Tissue samples were analysed for toxic contaminants by Ehime University in Japan. The results showed that the principal cause of the mass mortality was the same strain of canine distemper virus as had been isolated in 1997. The toxicology analysis found that the organchlorine (mainly DDT and PCBs) were in general only moderately high, and there was actually no evidence for a causative link between pollutant levels and death from the virus.
Scientific papers on Caspian seals arising from the CEP start-up initiative and Ecotox project may be downloaded from this page.
Following the Ecotox project, a new project began with the aim of estimating the true present size of the Caspian seal population. The population is believed to have been well over a million seals by the turn of the 20th century, but was believed to have declined drastically, mainly die to unsustainable hunting during the late 19th and 20th centuries. The prevailing figure for the current population size at the turn of the 21st century was about 400,000, but there was no hard evidence for this.
A new project to carry out aerial surveys of the breeding population on the winter ice-field was launched in 2005, funded by the Global Environment Fund (GEF) under the CEP umbrella and supported by Agip KCO. The project is known as CISS (Caspian International Seal Survey) and is currently being coordinated by Dr Simon Goodman at Leeds University.The first CISS survey found evidence for a breeding population of a little over 20,000 breeding females (and pups), which yielded an overall population estimate of a little over 100,000 - or about a quarter of the eariler estimates. Annual surveys then continued until 2012, funded by Agip KCO - with the overall number of pups on the ice fluctuating from year to year, but usually slightly lower than the original 2005 result. Thus we are fairly confident that the population has declined by at least 90% since around 1900, primarily due to hunting..
Alongside the annual aerial surveys of the breeding population, two other seal projects were also funded by Agip KCO. One was a satellite telemetry project (2008-present) to determine seal movements, foraging areas and migration corridors. This has been very successful with exciting results - due to be published shortly. The other project was an investigation into the impact of icebreakers, servicing the oil platforms, on breeding seals, particularly mothers and pups, on the ice from late January to early March. The general behaviour of mothers and pups was also studied from icebreakers - and all this work is due to be published shortly. Links to a conference presentation on breeding behaviour may be found below.
Wilson et al. 2012. Breeding behaviour and pup development in the Caspian seal, pages 157-160.
Caspian-wide seal conservation projects also continued between 2006-12, initially under the UK Darwin Caspian seal project (to identify and eliminate threats to the Caspian seal, 2006-10) and then under the GEF Caspeco project (2009-12) to develop a plan for creating special protected areas for seals throughout the Caspian. In the course of this project, the very serious threat to seals from fisheries by-catch was quantified, indicating that probably several thousand seals die in fishing nets throughout the Caspian every year, with many skins being taken and processed in both legal and illegal operations in Dagestan.
Papers published from the CEP and Ecotox projects and the CISS surveys and co-authored by S. Wilson of Tara Seal Research may be obtained from the references below.
Mass Die-Off of Caspian Seals Caused by Canine Distemper Virus
Seamus Kennedy, Thijs Kuiken, Paul D. Jepson,Robert Deaville, Morag Forsyth, Tom Barrett, Marco W.G. van de Bildt,
Albert D.M.E. Osterhaus, Tariel Eybatov, Callan Duck, Aidn Kydyrmanov, Igor Mitrofanov,Susan Wilson. Emerging Infectious Diseases 6(6), 637-639. (2000)
The 2000 Canine Distemper Epidemic in Caspian Seals (Phoca caspica): Pathology and Analysis of Contributory Factors
T. KUIKEN, S. KENNEDY, T. BARRETT, M.W. G. VAN DE BILDT, F. H. BORGSTEEDE, S. D. BREW, G. A.
CODD, C. DUCK, R. DEAVILLE, T. EYBATOV, M. A. FORSYTH, G. FOSTER, P. D. JEPSON, A. KYDYRMANOV, I. MITROFANOV, C. J. WARD, S. WILSON, AND A. D. M. E. OSTERHAUS. Vet Pathol 43:321–338 (2006).
Pup Production and Breeding Distribution of the Caspian Seal (Phoca caspica) in Relation
to Human Impacts. Tero Harkonen, Mart Jussi, Mirgaly Baimukanov, Anders Bignert, Lilia Dmitrieva, Yesbol Kasimbekov, Mikhail Verevkin, Susan Wilson and Simon J. Goodman. Ambio 37 (5). (2008).
Collapse of a Marine Mammal Species Driven by Human Impacts
Tero Harkonen, Karin C. Harding, Susan Wilson, Mirgaliy Baimukanov, Lilia Dmitrieva, Carl Johan Svensson, Simon J. Goodman. PLoS ONE 7(9): e43130. doi:10.1371/journal.pone.0043130 (2012)
Assessment of Caspian Seal By-Catch in an Illegal Fishery Using an Interview-Based Approach
Lilia Dmitrieva, Andrey A. Kondakov, Eugeny Oleynikov, Aidyn Kydyrmanov, Kobey Karamendin, Yesbol Kasimbekov, Mirgaliy Baimukanov, Susan Wilson, Simon J. Goodman. PLoS ONE 8(6): e67074. doi:10.1371/journal.pone.0067074.
The Role of Canine Distemper Virus and Persistent Organic Pollutants in Mortality Patterns of Caspian Seals (Pusa caspica)
Susan C. Wilson, Tariel M. Eybatov, Masao Amano, Paul D. Jepson, Simon J. Goodman. PLoS ONE 9(7), e 99265. https://doi.org/10.1371/journal.pone.0099265 (2014)
Inter-year variation in pup production of Caspian seals Pusa caspica 2005–2012 determined from aerial surveys
Lilia Dmitrieva, Tero Härkönen, Mirgaliy Baimukanov, Anders Bignert, Ivar Jüssi, Mart Jüssi, Yesbol Kasimbekov, Mikhail Verevkin, Vadim Vysotskiy, Susan Wilson, Simon J. Goodman1, Endang Species Res 28: 209–223,
doi: 10.3354/esr00689 (2015)
Individual variation in seasonal movements and foraging strategies of a land-locked, ice-breeding pinniped
Lilia Dmitrieva, Mart Jüssi, Ivar Jüssi, Yesbol Kasymbekov, Mikhail Verevkin, Mirgaliy Baimukanov, Susan Wilson, Simon J. Goodman. Mar Ecol Prog Ser 554: 241–256, doi: 10.3354/meps11804. (2016)
Breeding behavior and pup development of the Caspian seal, Pusa caspica
Susan C. Wilson, Evgeniya Dolgova, Irina Trukhanova, Lilia Dmitrieva, Imogen Crawford, Mirgaliy Baimukanov, and Simon J. Goodman Journal of Mammalogy, 2017, 98(1):143–153, DOI:10.1093/jmammal/gyw176. Published online November 15, 2016.
Assessment of impacts and potential mitigation for icebreaking vessels transiting pupping areas of an ice-breeding seal (including Supplementary material: Appendix D. Development of integrated mitigation measures for icebreaker impact on breeding seals in the Caspian Sea)
Susan C. Wilson, Irina Trukhanova, Lilia Dmitrieva, Evgeniya Dolgova, Imogen Crawford,
Mirgaliy Baimukanov, Timur Baimukanov, Bekzat Ismagambetov, Meirambek Pazylbekov,
Mart Jüssi, Simon J. Goodman. Biological Conservation 214 (2017) 213–222. http://dx.doi.org/10.1016/j.biocon.2017.05.028
Unfortunately the international CISS team (including Sue Wilson) was unable to continue aerial surveys over the ice or studies of breeding seals on the ice after 2012. Earlier information on the Caspian seal project is available on our Caspian seal website, which is currently being revised and updated.