ISSN 10630740, Russian Journal of Marine Biology, 2010, Vol. 36, No. 1, pp. 43–46. © Pleiades Publishing, Ltd., 2010.
Original Russian Text © I.M. Tiunov, A.Yu. Blokhin, 2010, published in Biologiya Morya.
Seagulls, like all marine colonial birds, play a
noticeable role in the oceanic biocenoses. They are
also important as indicators of productive zones of the
sea and as shore scavengers. In the last decade, exten
sive accounts of seabirds of the Sea of Okhotsk and the
Tatar Strait have been published [5, 8]; nevertheless,
this region still remains inadequately studied. Thus,
some areas of the coastline or some islands have not
been visited by ornithologists, or otherwise there is
only incomplete and fragmentary information con
cerning the abundance and species composition of
seabirds in such areas. Moreover, observations on the
dynamics of abundance of previously known colonies
of seabirds are needed to reveal the changes that have
been caused by natural processes and human activity.
Starting in the 1930s, the coast of the Tatar Strait
was turned into a defense line with a specific regime of
secrecy. Only in 2002, small boats of the local people
were allowed to sail, without hindrance, over Chikh
achev Bay and the Tatar Strait. Until that time, a strict
border regime defended the coastal zone against tres
passing. In the last decade, economic activity has
expanded in the northern Tatar Strait. Here, the laying
of gas and oil pipelines from Sakhalin Island and the
construction of oilloading complexes and oilpro
cessing plants are now in progress.
In 2001 these facts stimulated us to survey the pre
viously unvisited Chikhachev Bay and subsequently to
perform annual observations on the status of bird col
onies, as well as counts of the numbers of larids on the
islands in the Chikhachev Bay and on the Glazenap
and Popov islands situated northward [2, 3]. In 2008,
we surveyed Ushkanii Island on Lake Bolshoe Kizi
OF STUDY AREA
Ustrichnyi Island is situated in Chikhachev Bay.
The closest distance to the mainland is 2.3 km, to De
Kastri (urbantype settlement) 4.5 km. The area of the
upper terrace is 622137 m
. The greatest length is
330 m and the greatest width is 190 m. Almost the
whole of the island is covered by a forest massive. Its
rock cliffs are up to 100 m high.
Bazaltovyi Island is situated in Chikhachev Bay.
The shortest distance to the mainland is 800 m, to De
Kastri 2.1 km. The area of the upper terrace is
. The greatest length is 470 m and the great
est width is 390 m. The upper terrace is covered by
burnt fallen wood. Its rock cliffs are up to 20 m high.
Glazenap Island is situated south of Cape Nevel
skoi. The distance to the mainland is 650 m and the
distance to the nearest settlement (Vidanovo) is
12.6 km. The strait depth at the lowest low tide is
0.5 m. The area of the upper terrace is 34090 m
greatest length is 260 m and the greatest width is
170 m. Almost the whole of the island is covered by a
forest massive. Its rock cliffs are up to 70 m high.
Popov Island is situated in the southern Nevelskoi
Strait. The distance to the shore is 2.8 km and to the
nearest settlement (Nigir’), 9.5 km. The area of the
Dynamics of the Abundance of Seagulls (Charadriiformes: Laridae)
in the Northern Tatar Strait
I. M. Tiunov
and A. Yu. Blokhin
Institute of Biology and Soil Science, Far East Division, Russian Academy of Sciences, Vladivostok, 690022 Russia;
Environmental Company of Sakhalin, YuzhnoSakhalinsk, 693007 Russia
Received September 15, 2009
—Field observations on colonies of seagulls (Laridae) were carried out annually on islands of the
northern Tatar Strait during 2001–2008. A general tendency towards a reduction in the number of nesting
birds was observed on all islands surveyed. The anxiety factor and direct destruction of bird eggs and fledglings
caused the whole or the greater part of colony to migrate to “quieter” sites on islands or the continental coast.
The replacement of
was observed in sites where the two species nest in
neighborhood. Nesting specimens of
were found on islands of Lake Bolshoe Kizi, suggesting
that the birds are in search of alternative nesting places that are less accessible to humans and predators.
seabirds, colonial nesting birds, Laridae, Tatar Strait, Chikhachev Bay.