Volume 16 - N. 2
- Avocetta n.16 (2) - 1992
Conservation programme for Audouin's Gull in the Chafarinas Islands
Alvarez G.Abstract Read Article Download
I review population changes from 1976 to 1992 in the Audouin’s Gull colonies of Chafarinas
Islands National Game Sanctuary. Earlier studies showed that after increasing rapidly between 1976
and 1983, the Audouin’s Gull population stabilized, and breeding success decreased until 1985. This
decrease was linked to a rapid increase in Yellow-Iegged Gulls over the same period, and was attributed
to predation and to limited nesting sites. Yellow-Iegged Gulls have been controlled since 1987 by
narcotizing adults and sterilizing eggs. After 6 years culling, the Yellow-Iegged Gull population and
the breeding success of Audouin’s Gulls were similar to those of 1983, but the breeding Audouin’s
Gull pairs had doubled during the same periodo It is suggested that immigration of Yellow-Iegged Gulls
reduces the effectiveness of culling. The rat population may also limit the breeding success of the
Protection of Cory's Shearwater Calonectris diomedeaby Iimitation of a population of Feral Rabbits Oryctolagus on the Frioul Archipelago (Marseilles, France)
BAYLE P. and FERNANDEZ O.
Les programmes de marquage de Laridae avec bagues colorées en Mediterranée
BOLDREGHINI P., MEININGER P. L. and SANTOLINI R.
The use of salinas by breeding Charadriiformes: two italian cases
BOLDREGHINI P., MONTANARI F. L., TINARELLI R.
Birds and habitat conservation on Chios, Greece
CHOREMI J. and SPINTHAKIS E.Abstract Read Article Download
In this attempt to describe birdlife in Chios Archipelago we record ed 211 species, most
of which are migrants and visitors. Large concentrations of birds appear during migration and suffer
a heavy hunting pressure (shooting and liming). The most important bird areas are Psara and Dotia
with mainly bushy vegetation. The authors propose the establisment of a marine and island park in
Psara-Antipsara archipelago for the protection of birds during migration.
Habitat use in Yellow-Iegged Gull(Larus cachinnans michahellis) coastal wetland coloniesof North-East Greece
GOUTNER V.Abstract Read Article Download
Yellow-Iegged Gull habitat use was studied at two colonies situated on lagoon islets (Lafri
and Karatza) in North-East Greece. At the Lafri colony most nests (74.3070) were in high cover (>70%,
overall average 78070). Sand dune and ruderal vegetation were avoided in preference for halophytic
communities of Halocnemum strobilaceum (HS) and Halimione portulacoides – Arthrocnemum
jruticosum (HP-AF); both were used in proportion to their availability. Both vegetation cover and
type were important for nest placement and spacing. At the Karatza colony most nests (78.1 070) were
in high cover (average 85 070). The most important plant communities were Asparagus tenuifolius
(dominant) and HP-AF; both were used in proportion to their availability. In this colony vegetation
cover seemed to be more important than vegetation type. This allowed a better breeding synchronization
than at Lafri. Aspects of Yellow-Iegged Gull habitat use in the wider area are discussed.
Armenian Gulls Larus armenicus in Egypt, 1989/90,with notes on the winter distribution of the large gulls
MEININGER P.L. and S0RENSEN U.G.Abstract Read Article Download
During a survey of Egyptian wetlands between December 1989 and late May 1990 significant
numbers of Armenian Gulls Larus armenicus were observed. Total winter count was 442, and the
species was present until early April , It was found to be relatively common along the Mediterranean
coast east of the Damietta branch of the Nile, and in marine habitats of the three lagoons along this
coast. Small numbers were seen along the Suez Canal and the Red Sea coast. No Armenian Gulls
were found in any of the inland waters. Other large gulls counted in winter included Yellow-Iegged
Gulls L. cachinnans (2340), Lesser Black-backed Gulls L. fuscus (120; including the first Egyptian
record of L. f. heuglini), and Great Black-headed Gulls L. ichthyaetus (35).
The nesting by the Herring Gull (Larus argentatus) in the Towns and Villages of Bulgaria
Status and migration of the Siender-billed Gull (Larus genei) in Bulgaria
NANKINOV D.N.Abstract Read Article Download
The earliest Slender-billed Gulls arrive in Bulgaria after July 5. Some 72.70/0 migrate to
the Mediterranean in August-October. A tiny number, 1.0 to 2.2% of the birds spend the winter and
spring in Bulgaria. The Black Sea is the spring flight route. Nesting by the Slender-billed Gull may
be expected in Lake Atanassovsko.
The colony of the Audouin's Gull at the Ebro Delta
ORO D. and VILLALTA A.M.Abstract Read Article Download
We describe the Audouin’s Gull colony established in the Ebro Delta (NE Spain) since
1981. The amazing growth of this colony, which is now the largest in the worId, with about the 60070
of the species’ world population, was favoured in our view both by the complete protection of the
breeding areas from human interference since 1987, and by its high reproductive success (maximum
2.01 chieks/pair in 1988). This breeding success is the highest reeorded in Audouin’s Gull eolonies
studied to date, and it seems 10 be due to the high availability of feeding resourees (demersal fish)
from activities by the loeal fishing fleet. Moreover, disturbanee by breeding Yellow-legged Gulls was
low. Changes in these faetors eould break the eolony stability, as happened with the moratorium on
inshore fishing in 1991 and 1992. The fragility of the Audouin’s Gull population is mainly due to
its generalized low breeding success in the main colonies, and its concentration in a few large eolonies.
Pesticide residues in Cory's Shearwater eggs (Calonectris d. diomedea)
RISTOW D., . HAORICH J., BAUM F. and WINK M.Abstract Read Article Download
Oeserted eggs of Cory’s Shearwater from a colony off Crete were analyzed for chlorinated
hydrocarbon content. Substantial concentrations of DDE and PCBs were found. High concentrations
of DDE are correlated with those of PCBs. Almost at the top of the Mediterranean food chain, Cory’s
Shearwater is a good bioindicator for the Mediterranean.
Does Cory's Shearwater breed every yearor is there evidence for a sabbatical?
RISTOW D., SWATSCHEK I. and WlNK M.Abstract Read Article Download
A colony of Cory’s Shearwater (Ca/onectris d. diomedea) was studied for severa l years
on a rocky island off Crete. Care was taken to distinguish breeding birds. including unsuccessful breeders,
from the non-breeding population. From yearly retrap data of breeding birds it is concluded that they
make a breeding attempt every year and do not take a sabbatical. This result differs from the finding
that the Atlantic subspecies borea/is shows a sabbatical frequency of 7″10 (Mougin et al. 1985).
The Dnestr Delta Black Sea: ornithological importance,conservation problems and management proposals
Schogolev I.Abstract Read Article Download
The Dnestr Delta is one of the most intaet wetland eeosystems in the Blaek Sea. In a total
area of 220 krn-, dominated by extensive reedbeds, important populations of waterbirds nest in
eolonies, some of them in numbers of international signifieanee. The seasonal floods of the river are
the key faetor for the funetioning of this wetland eeosystem, but human intervention and the eonstruetion
of a hydroeleetrieal dam are now having serious environmental impaet on the delta. A management
plan for the waters of the river should be fully implemented and the delta should be designated as
a National Park in order to halt and reverse its degradation.
The Lagoon of Venice: a premigratory crossroads for Little Terns Sterna albifrons
SERRA L., PANZARIN F., CHERUBINI G., CESTER D. and BACCETTI N.
Eradication of the Brown Rat from the Toro Islets (Corsica):remarks about an unwanted colonizer
THIBAULT J.C.Abstract Read Article Download
Between 1986 and 1988 the Brown Rat (Rattus rattus) was introduced onto the Toro Islets,
an important piace for breeding birds (Cory’s Shearwater Ca/oneetris diomedea, Storm Petrel
. Hydrobates pelagieus, Pallid Swift Apus pallidus, and other birds). The aims of this paper are: (i)
to describe and discuss the method used to eliminate the rats from these islets in 1991-1992, (ii) to
show the consequences of the Brown Rat’s introduction on seabirds on Corsican islets. Keeping islands
free from rats appears to be a major target for the conservation of seabirds in the Mediterranean.
Known population and distribution of cormorants,shearwaters and Storm Petrels in the Mediterranean
ZOTIER R., THIBAULT J.C. and GUYOT I.Abstract Read Article Download
Five species of Procellariidae, Hydrobatidae and Phalacrocoracidae breed in the
Mediterranean: the Cory’s Shearwater Caloneetris diomedea (57,000-76,000 breeding pairs), the
Mediterranean Shearwater Puffinus yelkouan (18,000 known breeding pairs), the Storm Petrel
Hydrobates pelagieus melitensis (8,500-15,000 known breeding pairs), the Shag Phalaeroeorax aristotelis
desmarestii (about 7,000 breeding pairs) and the Cormorant Phalaeroeorax earbo (8,000 breeding pairs).
Large populations of seabirds occur on the Balearics archipelago, in the Sicilian channel and in the
north of the Tyrrhenian Sea. The status of birds in the Adriatic, Ionian and Aegean Seas needs to
be c1arified by further survey.
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