Revue internationale d'écologie méditerranéenne International ...

The Sardinian newt: an endemic
on the brink of extinction?
ecologia mediterranea, tome 29, fascicule 2, p. 249-258
FAITS DE CONSERVATION EN MÉDITERRANÉE / MEDITERRANEAN CONSERVATION NEWS ◆
In the last few decades, there has been evidence of a widespread
decline of amphibian populations, often without obvious correlation
to human impact and environmental degradation. Mediterranean
regions comprise almost intact areas as well as heavily impacted habitats,
and a biodiverse and rich in endemism herpetofauna, represented
also by rare and endangered species. One example is the Sardinian
mountain newt, Euproctus platycephalus (also known as Sardinian
brook salamander), classed by IUCN as critically endangered and
also listed in Appendix II/Annexe II of the Bern Convention. Despite
its critical conservation status, the Sardinian newt is poorly known
and, until recently, poorly studied. I have dedicated three years of
research to highlight the actual distribution (Lecis & Norris, 2003),
the habitat ecology, and the population genetic structure (Lecis &
Norris, 2004a,b) of this endemic species, found only in streams, small
lakes and pools of the mountains of Sette Fratelli, Gennargentu and
Limbara on the island of Sardinia (Italy).
In the paper recently published in Biological Conservation
(Lecis & Norris, 2004a), we describe the application of habitat-based
statistical models relating patterns of presence and
absence of this species to habitat variables, trying to understand
the causes of newt population declines. Habitat protection and
the preservation of entire ecosystems are of prime importance
for maintaining amphibian populations. Habitat suitability has a
direct influence on the survival and reproduction of individuals,
and consequently on the viability of populations. Our ecological
study represents a first attempt to statistically relate habitat
characteristics to Sardinian newt occurrence and persistence, in
Mediterranean areas where human impact is still overall limited
although present. Reported declines of newt populations are not
yet supported by quantitative data, however, they are perceived or
suspected across the species’ historical range. Possible local threats
to the species are the drainage and fragmentation of the habitat,
due to prolonged drought (many streams in Sardinia are partially
or completely dry during the summer), and the reduction of water
level on the island due to increasing demand for human use; also
the introduction of trout (Salmo trutta) in the majority of water
courses for fishing purposes (trout may predate on newt larvae
and eggs) could play a role, as well as the use of illegal fishing
methods, and water pollution. Herpetological reserves should be
created to protect sites inhabited by newts in each mountain system,
and a monitoring program should be promoted to support
the local conservation of this endemic urodele.
For more information, read:
— LECIS R., NORRIS K., 2003. Geographical distribution
of the endemic Sardinian brook salamander Euproctus platycephalus
and implications for its conservation. Herpetological Journal, 13(3):
121-124.
— LECIS R., NORRIS K., 2004a. Habitat correlates of distribution
and local population decline of the endemic Sardinian newt
Euproctus platycephalus. Biological Conservation, 115, 303-317.
— LECIS R., NORRIS K., 2004b. Population genetic diversity of the
endemic Sardinian newt Euproctus platycephalus: implications for
conservation. Biological Conservation in press.
ROBERTA LECIS
VIA STEFANO CAGNA 66, 09126, CAGLIARI, ITALY
LAB.GENETICA, ISTITUTO NAZIONALE FAUNA SELVATICA,
VIA CÀ FORNACETTA 9, 40064, OZZANO (BO), ITALY
TEL.: +393282779966
EMAIL: ROB Y112@YAHOO.COM
Summarizing five years of a hacking programme for the
conservation of Audouin’s gull in the Valencian region
In 1998, the government of the Valencian region (Eastern
Spain) was partially granted by the EU to implement a LIFEnature
project addressed to the restoration of island habitat and
the protection of five seabird species of conservation concern in
Europe. One of the main actions of the project was the launching
of a hacking programme to establish a new colony of Audouin’s
gull Larus audouinii at the island of Benidorm. This small (6.5 ha.)
island, located right off the city of Benidorm (Alicante), was chosen
owing to its strategic location between two large colonies of
the species, those of the Ebro Delta (Tarragona) and Grossa
Island (Murcia). Considering that roughly 70% of the known
world population of Audouin’s gull is concentrated in just two
colonies (Ebro Delta and Chafarinas Islands), it is important to
count with a large number of small colonies as it reduces the
vulnerability of the species making less likely a possible extinction
if main colonies face stochastic catastrophic events. The hacking
programme started in 1999 and has been implemented annually
since that date. During the first two years chicks came from eggs
from the Columbretes archipelago colony (Castellón), reared in
captivity. However, from 2001 on, eggs and chicks come from
the Ebro Delta colony and the latter remain in captivity a short
period before being moved to the hacking facilities on the island.
Overall, 183 fledglings have been successfully released so far.
Considering only the cohorts of 1999 and 2000, because birds
released do not recruit typically until their third year of age, 20%
of the birds released have been observed back in the island. Birds
seem to be homing to the traditional wintering quarters of the
species because two ringed birds were recovered at Morocco
and Senegal. However, recruits seem to show a low fidelity to
the island as the percentage of birds resighted in a given year is
only half the number of birds resighted the previous year. This
low haunt for the island is probably caused by the unfavourable
ratio of returning Audouin’s gulls to breeding yellow-legged gulls
Larus cachinnans (ca. 500 pairs). Some four-year birds have shown
displays and even tried to build a nest but agonistic interactions by
yellow-legged gulls probably prevent their settlement. A new LIFE
project has been granted recently to the Valencian government
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