Blakiston's Fish Owl Program

The Blakiston's fish owl is endangered, and perhaps the largest owl in the world.  There are thought to be less than 1000 pairs of these birds remaining in the wild, with very few individuals held in captivity.  Found only in northeast Asia, this secretive species has a fragmented distribution in the remote forests of northern Japan, the Russian Far East, and northeastern China.  Despite being the focus of strong conservation interest, study of Blakiston's fish owls is complicated by difficulties associated with data collection in the wild areas where the owls are found.  As a result, the biology of Blakiston's fish owls remains largely unknown.  This is particularly so in Russia, where this aquatic prey specialist manages to persist year-round in a climate frozen for months on end.  From a conservation perspective it is important to establish baseline ecological data for the species, as their apparent need for old-growth, riverine habitat is in direct conflict with logging interests in the region.  Without a clear understanding of habitat use, sound conservation plans for Blakiston's fish owls cannot be developed.  Therefore, our primary goal is to develop conservation recommendations based on clearly defined habitat requirements of this species.  This goal will be achieved by an intensive telemetry study in Primorye, Russia, a region rich with natural resources and charismatic wildlife, and with a strong WCS presence.  We will capture a sample of fish owls and fit them with small harness-mounted transmitters, which will allow us to monitor their movements throughout the year.  This information will be critical to the development of effective conservation and management plans.

The Human Aspect
Blakiston’s fish owls have been recorded in several of Primorye’s zapovedniks and zakazniks (two types of Russian protected areas), but nearly all known nest territories (>95%) fall outside the borders of existing protected areas.  Therefore, management of habitat outside protected areas is critical for Blakiston’s fish owl conservation, and any such plans must include the land-use needs of local communities.  Education of local populations about the species will also greatly aid Blakiston’s fish owl conservation, as most causes of mortality are human-related and easily avoided. 

Threats
Two cases of predation (one by an Asiatic black bear, the other by a Eurasian lynx) are the only known sources of Blakiston’s fish owl mortality not directly tied to human activity.  Unlike Amur tigers, who are poached in the region for commercial gain, most fish owls die needlessly when they become entangled and drown in fishing nets, are captured in hunter snares, or are simply shot for sport.  Additionally, given their high fat content (particularly in the months leading up to winter), Blakiston’s fish owls were once prized as a food source by the indigenous Udege peoples, but this practice seems to be less common now.  In addition to poaching, habitat loss due to logging in old-growth riverine forest (much of it illegal) is also a significant threat.  Although a resident pair of Blakiston’s fish owls seems to occupy no more than 10 km2 as a home range, they have very specific habitat requirements.  Most known Blakiston’s fish owl nests have been found in natural tree cavities. Many fish owl territories have only a handful of such old-growth trees large enough to support a nest, and if these few trees are removed the owls will not breed.  Futhermore, the owls require productive stretches of river that remains unfrozen throughout the year to provide hunting habitat; not an simple requirement given the Russian Far East’s harsh winter climate.  

WCS Activities
WCS involvement with this species began in 2006, when we teamed up with the Amur-Ussuri Center for Avian Biodiversity and the Institute of Biology and Soils (Vladivostok) to travel to the remote Samarga River basin in northern Primorye to survey for Blakiston’s fish owls. What they found there is likely the greatest global concentration of Blakiston’s fish owls, with one pair found nearly every 4 km along the Samarga River. WCS has continued to supply funding and in-country support for the international team as they initiate their telemetry study in winter 2007, including providing housing at the newly-constructed WCS field office in Ternei, Russia, while the team works to capture Blakiston’s fish owls nearby. 

Important Next Steps
Over the next four years our research efforts will focus on:
· Monitoring movements of Blakiston’s fish owls using telemetry.                                    
· Developing models to help predict Blakiston’s fish owl occurrence across Primorye.
· Raising awareness about Blakiston’s fish owls both locally within Russia and internationally.
· Developing conservation recommendations for the creation of protected territories.
· Working with logging companies to minimize disturbance in Blakiston’s fish owl habitat.