Interview with Stavros Xirouchakis about Vultures on CreteDate of the interview: 10 February 2010 In this interview Stavros Xirouchakis talks about the conservation of the vulture on Crete.
Stavros Xirouchakis at feeding station
Stavros Xirouchakis: Out of the four European vulture species, only the Bearded Vulture (Gypaetus barbatus) and the Griffon vulture (Gyps fulvus) hold breeding populations on the island. The Cinereous vulture (Aegypius monachus) is a rare winter visitor (mainly immature birds) whereas the Egyptian vulture (Neophron percnopterus) is an autumn migrant. Markus Jais: How has their population developed during the last decades and how many pairs are there today?
Stavros Xirouchakis: The Bearded vulture population numbered about 9-10 breeding pairs in the early 1990s. However by the end of that decade only 4 pairs remained of which only two bred regularly every year. At present the species shows signs of recovery due to specific conservation measures undertaken during the present decade (e.g. artificial feeding , public awareness, designation of special protection areas). The current population consists of 5-6 breeding pairs, though the annual production is three fledglings. On the other hand the Griffon population was estimated at 200 breding pairs in late 1980s while presently it consists of 140 breeding pairs or an estimated 420 individuals. This population comprises the last relatively healthy population in the Balkans and the largest insular one worldwide.
Rangeland in south Crete - Asterousia Mountain, © Stavros Xirouchakis
Stavros Xirouchakis: Both vulture species depend exclusively on livestock and farming activities of humans. Considering that signs of domesticated animals on island go back as early as 7000 years ago we may conclude that vultures have co-evolved with agriculture in this part of the Mediterranean region. Markus Jais: How important is traditional livestock farming for vultures?
Stavros Xirouchakis: Free-ranging flocks and transhuman pastoralism hold a key-role position in the survival of vultures in Crete. Both species follow the spatial and temporal distribution of livestock, taking advantage of the traditional farming practices and open abattoirs. Not surprisingly all griffon colonies and Bearded vulture nests are located in middle-latitude areas (600-800m) so birds can forage optimally after following the flocks in their wintering rangelands. For instance the Bearded Vulture which is a typical mountainous species breeds at the lowest mean altitude in the world. Actually the lowest active Bearded vulture nest is situated at 300m. Markus Jais: Are there feeding places for the vultures like there are in Spain?
Stavros Xirouchakis: There are 7 feeding stations on the island that were established for the benefit of the Bearded Vulture. They consist of open areas over rocky outcrops or cliff walls of gorges. In these places livestock extremities are primarily deposited. On average 6 tonnes of food is deposited per year and an additional 15 kg/ year/ pair of pure meat (i.e. unskinned rabbits) is provided near to active nests when the chicks hatch. However three of these sites have been turned to conventional "vulture restaurants" (namely fenced areas that are provided with whole carcasses or offal and slaughter house remains) which are used by all avian scavengers. By this way young inexperienced Bearded vultures improve their foraging efficiency by following Griffons and Ravens.
Feeding station, © Stavros Xirouchakis
Stavros Xirouchakis: According to the EU regulations the disposal of dead animals in the field is prohibited. However most stock-breeders violate the law because transporting transporting and destroying (burning or burying) the carcasses is quite expensive or impractical in the the stony landscape of Crete. On the contrary they dispose carcasses in ditches or open waste dumps close to their farms. However free ranging animals still die in the open and are available to the vultures. Markus Jais: What are the main threats to vultures in Crete?
Stavros Xirouchakis: Although large carnivores are absent from Crete and no large scale anti-predator campaigns have ever been undertaken on the island, the use of poison baits for the extermination of stray-dogs and Ravens (Corcus corax) still takes place and poses the most serious threat to the vultures. Illegal shooting, though not so severe as in the past also takes its toll from the population. Other mortality causes are starvation of the young Griffons during the post-fledging period, drowning at sea or water reservoirs and quite lately collision with turbines in wind farms.
Lefka Ori Mountain, west Crete, © Stavros Xirouchakis
Stavros Xirouchakis: By a small sample of dead specimen that has been toxicologically analyzed, lead was insignificant. Besides vultures depend more on carrion originated from livestock than hunter kills. Actually as no big game exist on the island (i.e. deer, wild boars etc) lead poisoning is not expected to constitute a major threat for vultures in Crete. Markus Jais: How does the development of wind farms affect vultures and other raptors and will it get worse in the future?
Stavros Xirouchakis: Crete currently supports the only breeding population of Bearded Vultures in the Balkans and ca. 80% of the Greek Griffon vulture population. Furthermore it has been characterized as an area with very high wind-energy potential due to its mountainous and rugged terrain and the strong winds that prevail almost throughout the year. Although the number of vultures being killed in wind farms is relatively low (only four), this figure is certainly underestimated as no systematic monitoring of all of the existing wind farms has been carried out. I strongly believe that if the Special Protection Areas (SPAs) designated under the EU Birds’ Directive (79/409/EC) "open" to investors the interactions of vultures and wind turbines will dramatically increase. Markus Jais: What can be done to avoid vulture deaths through wind farms?
Stavros Xirouchakis: Only by two ways. First the exclusion of wind farms from protected areas and the vicinity of breeding sites (5 km) and second by their proper site planning in the rest of the island. I think that small-scale projects namely 5-10 turbines with adequate distances between them (so to leave flying corridors for the birds) would decrease the impact.
Psiloritis_Mountain, central Crete, © Stavros Xirouchakis <
Stavros Xirouchakis: Pastoralism has strong roots in the local culture and Crete constitutes one of the few agricultural areas in Greece where young people still prefer to get involved with animal husbandry. I think that the situation will change in the near future if specific socio-economical factors cease to persist (subside EU policy, land use changes, rangeland mismanagement etc). However, in any case, the available breeding and foraging habitat for the birds will certainly decrease due to the increase of human population and urban expansion. As a result a shrinkage of the vultures’ distribution and a lower local density are expected in the long term. Markus Jais: Which eagle species do breed in Crete and how is their situation today?
Stavros Xirouchakis: The Golden Eagle (Aquila chrysaetos) with a population of 16-22 breeding pairs and the Bonelli’s Eagle (Aquila fasciata) with 10-12 breeding pairs. Markus Jais: What was your most amazing experience with vultures?
Stavros Xirouchakis: There are a lot but I recall only one with great respect. I had climbed in one of the numerous peaks of the Lefka Ori National Park (there are 57 over 2000m) scanning around for Bearded Vultures. After 8 hours (ca. 14:00 p.m), a pair of Bearded Vultures showed up "whistling" and soaring over my head. The mustache and red eye-ring of the birds was visible with naked eye. In the same time a Golden Eagle was performing undulating flights at a distance of 500m ahead of me and 35 Griffons were gaining height over a gorge. On top of that I could also hear the sound made by the horns of two male Wild Goats (Capra aegagrus) fighting inside the gorge. This incident took place in atumn 1996 and I have never experienced anything similar in the 25 years I have been working in the field. Markus Jais: Stavros, thank you very much for the interview.