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Ecologically or Biologically Significant Areas (EBSAs)

  published: 12 Jun 2015

Coastal Waters of Chukotka

General Information
These waters are ice-covered for most of the year, however sea-ice conditions differ from west to east and from south to north. The coastal Chukchi Sea differs from the seas of the Siberian shelf by its increased pelagic primary production and the flux of carbon to the sea floor (Vetrov and Romakevich, 2011). Chaun Bay and other inlets and lagoons harbour kelp communities (Golikov et al., 1994; 2009), which significantly increase productivity in coastal areas compared to most part of the Siberian shelf seas. Benthic biomass in the coastal areas is high in protected bays and inlets (Sirenko et al., 2009; Denisenko, 2010; Denisenko et al., 2010). Some communities are particularly rare, i.e., the fucoid communities, kelp and mussel beds along the eastern shore of Chaun Bay, which are relics of the warmer Holocene conditions (Golikov et al., 1994). Shallow bays, with their specific regime, and the marshes along the coast serve as staging, moulting and nesting areas for numerous aquatic birds, including eiders, long-tailed ducks (Clangula hyemalis) and alcids (Gavrilo and Popov, 2011). In winter, most of the Chukotka Peninsula coastal zone forms an area of high concentration of ringed (Phoca hispida) and bearded (Erignathus barbatus) seals and their predators: polar bears (Ursus maritimus) (Belikov et al., 1998). The area also serves as a migration route for gray whales (Eschrichtius robustus) of the Californian-Chukchi population and bowhead whales (Balaena mysticetus).
The report on identifying Arctic marine areas of heightened ecological significance (AMSA IIc) revealed the importance of the coastal waters of the eastern part of the East Siberian Sea, i.e., Chaun Bay (Chaunskaya Guba, in Russian), and the coastal waters of the Chukotka Peninsula in the Chukchi Sea (AMAP/CAFF/SDWG, 2013: figures 8, 9 A and B; tables 13, 14). The IUCN/NRDC Workshop to Identify Areas of Ecological and Biological Significance or Vulnerability in the Arctic Marine Environment (Speer and Laughlin, 2011) identified an area named “Chukchi and Beaufort Sea Coast” as meeting nearly all CBD criteria. Based on subsequent analysis, emphasis was placed on the continuity of environmental conditions and changes in these conditions in this area, and hence they were combined in a single area meeting the EBSA criteria.
Description of the location
Arctic
The area extends from the western and northern extremities of Ayon Island in the East Siberian Sea, includes the Chaun Bay (Chaunskaya Guba, in Russian), Kolyuchin Bay (Kolyuchinskaya Guba, in Russian) and conventionally extends to 35 miles from the typical shore. It lies entirely within the jurisdiction of the Russian Federation (internal marine waters of inlets, territorial sea and the EEZ).
DISCLAIMER: The designations employed and the presentation of material in this map do not imply the expression of any opinion whatsoever on the part of the Secretariat concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries.
Area Details
The coastal zone of western and northern Chukotka extends from the large Chaun Bay with its own oceanographic regime in the East Siberian Sea to the south-western Chukchi Sea. It is not strongly impacted by the freshwater input of great Siberian rivers and maintains marine conditions except for a limited number of estuaries and lagoons. This is a shallow shelf area lying entirely within 50 m isobaths (usually less than 20 m). In the East Siberian Sea, stratification of coastal waters is generally weak but may increase owing to summer warming and surface transport of estuarine waters. The upper layer warms up in summer to 0 – 2° C but in the inner part of the Chaun Bay and other estuarine habitats temperature may increase to 4 – 8° C (Denisenko et al., 2010). Salinity of both surface and near bottom layers increases from west to east (28 psu in the bottom layer of the Chaun Bay and yet 32 psu in the De Long Strait) The current goes generally eastward, and part of the East Siberian water enters the Chukchi Sea through De Long Strait (Zalogin and Kosarev, 1999; Denisenko et al., 2010). Bottom topography is relatively even, and sediment is largely muddy sand in the East Siberian Sea and sand in the Chikchi Sea so that the proportion of mud particles generally decreases from Chaun Bay to the Chukchi Sea (Denisenko et al., 2010). In the inshore zone, hard substrates are also present (Golikov et al., 2009). The waters are covered with ice for most of the year, however sea ice conditions differ in the west to east and the south to north directions. On the eastern boundary the Ayon sea ice massif is formed, and in previous years, it persisted nearly year round. The bays and coastal waters have been covered with fast ice for about nine months a year to about the 10 m isobath, but the ice-free period has been increasing. The formation of flaw polynyas in the East Siberian Sea is a result of the interaction between the Arctic and the Siberian Anticyclones. Strengthening of the Arctic Anticyclone creates a wind pattern that facilitates the development of polynyas in the western part of the East Siberian Sea and, simultaneously, their depression in the eastern part of the East Siberian Sea and the Chukchi Sea. Development of polynyas in the Chukchi Sea is supported by cyclones originating in the Aleutian Low. The different and changing year-to-year interactions of the processes originating in these centres of atmospheric activity explain the inter-annual variability of polynyas in the East Siberian and the Chukchi seas. During warm years the Arctic Anticyclone weakens and shifts to the Canadian sector of the Arctic, resulting in the dominance of a system favouring polynya development in the Chukchi Sea. The monthly mean frequency of polynya occurrence is significant throughout the entire cold season of the year but it is on average lower than in the neighbouring Laptev Sea and varies from 41 to 89% (Gavrilo and Popov, 2011). The coastal Chukchi Sea is characterized by relatively high pelagic primary production most of whih reach benthic communities as a particle flux (Vetrov and Romakevich, 2011) and supports high benthic biomass used by sea ducks, walruses, bearded seals and grey whales. Protected inlets and lagoons harbour kelp communities (Golikov et al., 1994; 2009), which significantly increase productivity in coastal areas compared to most part of the Siberian shelf seas. Benthic biomass in the coastal areas is high in protected bays and inlets (i.e., Chaun Bay, Kolyuchin Bay and decreases by order of magnitude in the open areas (Sirenko et al., 2009; Denisenko, 2010; Denisenko et al., 2010).
The conditions in the area appear to be dynamic, and ecological processes are very sensitive to climate change, particularly variability in sea ice. An important potential threat is oil and gas exploration, which will begin in the coming decade. Part of the area (Kolyuchin Bay) is now protected within the new Beringia National Park, established in 2013.
References
AMAP/CAFF/SDWG, 2013. Identification of Arctic marine areas of heightened ecological and cultural significance: Arctic Marine Shipping Assessment (AMSA) IIc. Arctic Monitoring and Assessment Programme (AMAP), Oslo. 114 pp. Belikov S., Boltunov A., Belikova T., Belevich T.,Gorbunov Yu. 1998. Marine mammals. The distribution of marine mammals in the Northern Sea Route area. INSROP Working Paper No 118–1998.Oslo: The Fridtjof Nansen Institute. — 49 p. Belikov S.Ye., Boltunov A.N., Gorbunov Yu.A. 2002. Seasonal distribution and migrations of whales of the Russian Arctic based on results of long_term observations by aerial ice reconnaissance and drifting stations “North Pole”. In: A.A. Aristov, V.M. Belkovich, V.A. Zemsky, V.A. Vladimirov and I.V.Smelova (eds). Marine mammals (Results of researches conducted in 1995–1998). Moscow: Marine Mammals Council. — pp. 21–50. (In Russian). Bogoslovskaya L., Votrogov L., Krupnik I. 1982. The bowhead whale off Chukotka: migrations and aboriginal whaling. Reports of the International Whaling Commission, 32: 391–399. Denisenko S.G., Sirenko B.I., Gagaev S.Yu., Petryashov V.V. 2010. Bottom communities: structure and spatial distribution in the East Siberian Sea at depth more than 10 m. In: B.I. Sirenko, S.G. Denisenko (eds) Fauna of the East Siberian Sea, distribution patterns and structure of bottom communities. Explorations of the Fauna of the Sea, St. Petersburg, Zoological Institute of RAS, 66 (74), pp. 130–143 (in Russian). Denisenko S.G. 2010. Bioresources and production of zoobenthos in the East Siberian Sea. In: B.I. Sirenko, S.G. Denisenko (eds) Fauna of the East Siberian Sea, distribution patterns and structure of bottom communities. Explorations of the Fauna of the Sea, St. Petersburg, Zoological Institute of RAS, 66 (74), pp. 144–159 (in Russian). Gavrilo M.V., Popov A.V. 2011. Sea ice biotopes and biodiversity hotspots in the East Siberian Sea and the waters of Chukotka. In: V.A. Spiridonov., M.V. Gavrilo, N.G. Nikolaeva, E.D. Krasnova (eds) 2011. Atlas of the Marine and Coastal Biodiversity of the Russian Arctic. Moscow, WWF Russia, pp. 38–39. Golikov A.N., Sirenko B.I., Petryashov V.V., Gagaev S.Yu. 2009. Distribution of bottom communities in the Chukchi Sea from results of diving investigations. In: B.I. Sirenko (ed) Ecosystems and biological resources of the Chukchi Sea and adjacent areas. Explorations of the Fauna of the Sea, St. Petersburg, Zoological Institute of RAS, 64 (72), pp. 56–62 (in Russian). Sirenko B.I. 2009. The present state of investigations of the Chukchi Sea fauna. In: B.I. Sirenko (ed) Ecosystems and biological resources of the Chukchi Sea and adjacent areas. Explorations of the Fauna of the Sea, St. Petersburg, Zoological Institute of RAS, 64 (72), pp. 5–27 (jn Russian). Sirenko B.I. 2010. The present state of fauna investigations in the East Siberian Sea. In: B.I. Sirenko, S.G. Denisenko (eds) Fauna of the East Siberian Sea, distribution patterns and structure of bottom communities. Explorations of the Fauna of the Sea, St. Petersburg, Zoological Institute of RAS, 66 (74), pp. 5– 7 (in Russian). Sirenko B.I., Denisenko S.G., Gagaev S.Yu., Golikov A.A., Petryshov V.V. 2009. Bottom communities of the Chukchi Sea shelf at depth below 10 m. In: B.I. Sirenko (ed) Ecosystems and biological resources of the Chukchi Sea and adjacent areas. Explorations of the Fauna of the Sea, St. Petersburg, Zoological Institute of RAS, 64 (72), pp. 32–55 (In Russian). Spiridonov V.A. 2011. Biogeographical regionalization. Species diversity in the Russian Arctic seas: pelagic and sea ice biota, micro- and meiofauna. Macrobenthos: species diversity and group domination in the communities. In: V.A. Spiridonov., M.V. Gavrilo, N.G. Nikolaeva, E.D. Krasnova (eds) 2011. Atlas of the Marine and Coastal Biodiversity of the Russian Arctic. Moscow, WWF Russia, pp. 16-21. Vetrov A.A., Romankevich E.V. 2011. Primary production and fluxes of organic carbon to the seabed in the russian Arctic seas as a response to the recent warming. Oceanology, 51(2): 266–277.
Status of submission
Areas described as meeting EBSA criteria that were considered by the Conference of the Parties
  • dec-COP-12-DEC-22
Assessment of the area against CBD EBSA criteria
C1: Uniqueness or rarity Medium
There are no proven endemic species in the area, however several species have been described in the Chukchi Sea that are thus far known only in this region (Sirenko, 2009). Some communities are particularly rare, i.e., the fucoid communities, kelp and mussel beds along the eastern shore of Chaun Bay, which are relics of the warmer Holocene conditions and are maintained owing to the bay’s particular oceanographic regime (Golikov et al., 1994).
C2: Special importance for life-history stages of species High
In winter, most of the Chukotka Peninsula coastal zone and the polynyas adjacent to Wrangel Island form an area of high concentration of ringed (Phoca hispida) and bearded (Erignathus barbatus) seals and their predators: polar bears (Ursus maritimus) (Belikov et al., 1998). The system of polynyas and leads along the Chukotka coast serves as a spring migration path for cetaceans and seabirds, including eiders, long- tailed ducks (Clangula hyemalis) and alcids (Gavrilo and Popov, 2011). Shallow bays, with their specific regime, and the marshes along the coast serve as staging, moulting and nesting areas for numerous aquatic birds.
C3: Importance for threatened, endangered or declining species and/or habitats High
Gray whales (Eschrichtius robustus) of the Californian-Chukchi population migrating from their wintering grounds show up near the eastern coast of Chukotka in the second half of May. Most of them move to the Chukchi Sea in June. In this season both gray and bowhead (Balaena mysticetus) whales use polynyas and leads for migration. In summer and autumn bowhead whales forage and travel up to Wrangel Island and along the Chaunskaya Guba — as far as the ice edge allows (Bogoslovskaya et al., 1982; Belikov et al., 2002; Gavrilo and Popov, 2011); in particularly favourable years (when the ice massif to the west of Ayon Island breaks up in summer) bowhead whales may reach the New Siberian Islands (Gavrilo and Tretyakov, 2008).
C4: Vulnerability, fragility, sensitivity, or slow recovery High
Sea ice habitats are particularly sensitive to climate change; polar bears are particularly suffering from the melting of sea ice. Both sea ice habitats and bays are extremely vulnerable to oil spills that can potentially happen in the area if oil and gas exploration starts.
C5: Biological productivity High
The coastal Chukchi Sea is characterized by increased pelagic primary production and the flux of carbon to the bottom in comparison to the seas of Siberian shelf (Vetrov and Romakevich, 2011). Chaun Bay and other inlets and lagoons harbour kelp communities (Golikov et al., 1994; 2009), which significantly increase productivity in coastal areas compared to most part of the Siberian shelf seas. Benthic biomass in the coastal areas is high in protected bays and inlets (i.e., Chaun Bay, Kolyuchin Bay and decreases by order of magnitude in the open areas (Sirenko et al., 2009; Denisenko, 2010; Denisenko et al., 2010). However, in areas with moderate biomass, amphipods (Golikov et al.), which have a high P/B coefficient and biomass turnover rate, are particularly important.
C6: Biological diversity High
Species richness is relatively low in the East Siberian Sea, with some hotspots such as Chaun Bay (Golikov et al., 1994). Species richness increases in the Chukchi Sea, where many species of Pacific origin occur (Sirenko, 2009, 2010, Spiridonov, 2011; Spiridonov et al., 2011). The diversity of habitats, communities and ecosystems along the east-west and local gradients of oceanographical and sedimentological conditions is significant (Golikov et al., 1994; 2009; Sirenko et al., 2009; Denisenko et al., 2010).
C7: Naturalness High
This is a largely untouched area except for the localized impact of pollution in the Chaun Bay (Golikov et al., 1994).