My research

Broadly, I pursue three directions: spatial ecology, for example species distribution modeling and land use change; population dynamics, including time series analysis and PVA; and endangered species behavior.

Below are some examples of my projects.

Winter coat color in the warming world

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Snowshoe hare – one of the winter white species

About 22 species of mammals and birds change their coat color for the winter time: lemmings, arctic foxes, hares, ptarmigans and others. How will these species do when snow pack keeps shrinking? Some populations of winter white species are polymorphic, with white and brown winter phenotypes, and are likely to be under climate-mediated evolution pressure. I am analyzing distribution of polymorphic populations. It is interesting to see how polymoprhic zones of different species overlap and which covariates define those zones besides of snow cover duration. Analyzing climate-induced changes, I am studying how probability on an animal to be brown differ now as compared to before 1950s.

 

 

Eastern coyote impact on white-tailed deer at the Eastern US

Coyotes colonized the eastern US over the past few decades (look up, for example, very nice Sharon Levy’s article in Nature). However, it is unclear how coyotes affect local prey species. For example, white-tailed deer typically make up one third of the eastern coyote diet, but coyote impacts on white-tailed deer populations are controversial. In North and South Carolina, Alabama, Georgia and other eastern states there have been a few studies of coyote negative effects on deer populations. Also, there are few studies that coyote removal does not change deer population growth rate and abundance. Hence, I look at the relationship between coyote abundance and deer population growth rate over large areas using the arrival of coyotes in an area as a natural experiment.

Relevant papers and conference presentations

E.V. Bragina, R. Kays, J. Hody, C. Moorman, C. DePerno, L.S. Mills. No signal of eastern coyotes affecting white-tailed deer population growth at large scale. The Wildlife Society conference, Raleigh, NC. October 15-19, 2016. 

Population dynamics of large mammals in Eastern Europe and Russiawild_boar_kostromskaya

When a country goes through economic downturns, wildlife protection is not the first priority, and conservation might not be very efficient as a result of a weak law enforcement. The collapse of USSR in 1991 is a famous example of such a downturn, with poverty increasing up to 10 times in some post-soviet countries. I analyze time series of large mammals in the Eastern European countries and Russia to look at population dynamics in 1970s-2010s.

In Russia, population growth rates of several species was significantly different in 1990s from the rates in 1980s and 2000s. Wild boar, moose, and brown bear were declining in 1990s, and grey wolf was increasing. The magnitude of these changes is impressive. For example, the population of wild boar in Russia declined by half in the 1990s. Fortunately, wild boar numbers rebounded at the end of 2000s. However, a number of other species, for example moose, is still low.

My next step is the time series analysis of wildlife in Eastern Europe. The countries of former Soviet bloc went through post-socialism reforms with a different pace, some transitioning faster ans some more slow. Comparison wildlife dynamics in those countries is my current goal.

Relevant papers and conference presentations

E.V. Bragina, A.R. Ives, A.M. Pidgeon, T. Kuemmerle, L.M. Baskin, Y.P. Gubar, M. Piquer-Rodriguez, N.S. Keuler, V.G. Petrosyan, and V.C. Radeloff. 2015. Rapid declines of large mammal populations after the collapse of the Soviet Union. Conservation Biology, doi: 10.1111/cobi.12450

E.V. Bragina, A.R. Ives, L. Balčiauskas, S. Csányi, P. Hoetsky, O. Ionescu, K. Kysucká, J. Lieskovský, J. Ozolins, K. Perzanowski, T. Randveer, P. Štych, A. Volokh, C. Zhelev, E. Ziolkowska, A.M. Pidgeon, and V.C. Radeloff. Game population trends after the collapse of socialism in Eastern Europe. 100th meeting of Ecological Society of America, Baltimore, MD, August 9-14, 2015.

E.V. Bragina, A.R. Ives, A.M. Pidgeon, T. Kuemmerle, L.M. Baskin, M. Piquer-Rodriguez, N.S. Keuler, and V.C. Radeloff. Decrease of game mammal populations after Soviet Union collapse. 19th Annual Conference of The Wildlife Society, Portland, OR, October 13-18, 2012.

Population viability analysis of Caucasian tur Capra caucasica

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There used to be herds of 100-300 Caucasian tur. Now, we still see them in groups, though it is rarely more than 20-30 animals.

The Caucasian tur is an endemic of the Caucasus mountains: it lives on the border between Russia, Georgia, and Azerbaijan. According to IUCN, this species is endangered. Among threats to tur, poaching and livestock grazing are the main one. Poaching is more common at lower than at higher elevations, and accurate models must take this into account. However, in the future climate might have the greatest impact on this mountainous species, even if the local economy improves and poaching declines. In collaboration with local specialists, I am going to quantify threats and prioritize management actions for the tur.

 Habitat suitability analysis of the Caucasian bison

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In 1940s-1950s, first mountainous bison were reintroduced to Caucasus Nature Reserve. They had to adapt to mountains, for example, learn how to migrate up and down annually. For several years, the Reserve staff was chasing animals to bring them to higher elevation and then back, until they managed to do it by themselves.

Caucasian subspecies of European bison Bison bonasus caucasicus went extinct a century ago. However, hybridization of the last remaining Caucasian bison with lowland bison B. bonasus and American bison B. bison resulted in a viable herd of mountainous bison B. bonasus montanus. Now, several nature reserves in Russia are proud to have mountainous bison herds. However, it is necessary to keep reintroduction. In a collaboration with German and Russian scientists we developed a habitat suitability model to map potential sites for further reintroduction. More details are here.

Relevant papers and conference presentations

Bleyhl B., T. Sipko, S. Trepet, E. Bragina, P.J. Leitão, V.C. Radeloff, T. Kuemmerle. 2015. Mapping seasonal European bison habitat in the Caucasus Mountains to identify potential reintroduction sites. Biological Conservation, 191:83–92

Land use change

Bragina_et_al_fig2_sochiloggingConservation of wildlife requires protecting habitats. I use remote sensing to study land use change focusing on forest loss. Classification of Landsat images allows for estimating of forest loss inside and outside of protected areas and answer questions about the effectiveness of protected areas.

One of my study areas is the Western Caucasus, where much of the territory is protected to save endemic plants and animals. However, in spite of protection, many cases of forest loss, including illegal logging, are still reported in the region. Interestingly, the largest logging spot in 1985-2010 was within Sochi National Park, a place of Sochi Olympic Games – 2014.

In collaboration with Russian scientists we analyze clearcuts and selective logging in Altai krai, Western Siberia. Remnants of old-growth pine forests are concentrated within protected areas of Altai krai, but illegal logging is a big threat for these ecosystems. Unfortunately, pine timber is the most valuable one, and forest within protected areas suffers more that outside of them.

Relevant papers and conference presentations

Shchur A., E.V. Bragina, A. Sieber, A. Pidgeon, V. Radeloff. Detection of selective logging and clearcuts in Altai Krai, Western Siberia, using Landsat summer and winter imagery. Environmental Conservation, in press.

E.V. Bragina, V.C. Radeloff, M. Baumann, K. Wendland, T. Kuemmerle, A.M. Pidgeon. Effectiveness of protected areas in the Western Caucasus before and after the transition to post-socialism. Biological Conservation, 184:456–464.

Alcantara C., T. Kuemmerle, M. Baumann, E.V. Bragina, M. Dubinin, P. Griffiths, P. Hostert, J. Knorn, D. Müller, A. Prishchepov, A. Sieber, and V.C. Radeloff, 2013. Mapping the extent of abandoned farmland in Central and Eastern Europe using MODIS time series. Environmental Research Letters, 8(3):035035

E.V. Bragina, Wendland K, Baumann M, Sieber A, Kuemmerle T, Pidgeon AM, Alexandre P, Radeloff VC. Effectiveness of Russian protected areas before and after transition to post-socialism. International Congress on Conservation Biology, Baltimore, MD. July 21-25, 2013.

Vocal communication of endangered cranes

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White-naped crane male from Khingan Nature Reserve, Russia. Together with his mate, they built a nest right to our cabin. Every time we left our place or come back, we had to watch out for sharp claws and long beaks.

In the past, I studied vocal communication of cranes, including endangered Siberian Grus leucogeranus, Red-crowned crane  Grus japonensis, and white-naped cranes Grus vipio. Trying  various statistical approaches for discrimination of mating pairs and individuals, I found that crane calls are very individual and pair-specific. It provides a background for remote monitoring of these species.

Relevant papers and conference presentations

M.V. Goncharova, Klenova A.V., E.V. Bragina. 2015. Development of cues to individuality and sex in calls of three cranes species: when is it good to be recognizable? Journal of Ornithology, 33(3) 165-175

Klenova A.V., M.V. Goncharova, E.V. Bragina, and T.A. Kashentseva. 2014. Vocal development and voice breaking in Demoiselle Cranes (Anthropoides virgo). Bioacoustics, 23(3):247-265

Bragina E.V., I.R. Beme. 2013. Sex and individual features in the long-range and short-range calls of the white-naped crane. Condor, 115(3):501-507

Bragina E.V., I.R. Beme. 2010. Siberian crane duet as an individual signature of a pair: comparison of visual and statistical classification techniques. Acta Ethologica, 13 (1) P. 39-48 doi: 10.1007/s10211-010-0073-6