|Scientific Name:||Puffinus mauretanicus|
|Species Authority:||Lowe, 1921|
|Taxonomic Notes:||Puffinus yelkouan (Sibley and Monroe 1990, 1993) has been split into P. yelkouan and P. mauretanicus following Brooke (2004).|
|Red List Category & Criteria:||Critically Endangered A4bcde ver 3.1|
|Reviewer/s:||Butchart, S. & Symes, A.|
|Contributor/s:||Andrews, D., Arcos, J., Blasco, J., McMinn, M., Oro, D., Porter, R. & Tanner, K.|
This species has a tiny breeding range and a small population which is undergoing an extremely rapid population decline owing to a number of threats, in particular predation at breeding colonies by introduced mammals and at-sea mortality as a result of fisheries by-catch. Population models predict an extremely rapid decline over three generations (54 years), qualifying the species as Critically Endangered. However, this assumption was based on the existence of a population of c. 2,000 breeding pairs, which could have been underestimated according to recent population estimates and records at sea, plus a recent re-evaluation of some colonies (i.e. increased accuracy in the estimates). Updated population viability analysis to re-evaluate the species's status is planned, incorporating recent population estimates and improved demographic data. Should this analysis reveal that the species is declining at a more moderate rate, this species will warrant downlisting.
|Range Description:||Puffinus mauretanicus breeds in the Balearic Islands, Spain. In 2009, the breeding population of the Balearic Shearwater was last estimated in 2009 at 3,193 breeding pairs (Arcos 2011a). This figure is significantly larger than previous estimates of 2,000-2,400 pairs recorded in 2005 (Jones et al. 2008) but this is primarily due to increased survey effort (better prospecting of known breeding sites plus discovery of new sites) and does not reflect a genuine increase of the population. The islands of Mallorca have 900 pairs; Cabrera 449 pairs; Menorca 405 pairs; Ibiza 747 pairs and Formentera 692 pairs (Arcos 2011a). The world population was until recently believed to number 8,000-10,000 individuals (Louzao 2006a, Wynn and Yésou 2007), however recent winter at-sea surveys and counts from Gibraltar of post-breeding birds leaving the Mediterranean suggest the total population may in fact lie within in the range 20,000-30,000 individuals (Arcos 2011b). This is supported by a count of at least 16,400 individuals off Valencia in December 2009 (Aleixos 2012). Reasons for the discrepancy between breeding and non-breeding population estimates are unclear, but it is most likely that this species has a particularly large floating population of immatures and non-breeders. On Cabrera Island, 60% of the colonies have disappeared in the last few decades, while colonies on Formentera have experienced a strong decline in recent years, from more than 1,500 breeding pairs in the early 1990s to less than 1000 pairs in 2001 (Ruiz & Martí 2004) and 692 pairs in 2003-2006 (Arcos 2011a). Population viability analysis has shown that in the presence of environmental and demographic stochasticities, mean extinction time for the world population was estimated at 40.4 years, and mean growth rate showed a 7.4% decrease each year (Oro et al. 2004). However, this model was run using the earlier population estimate of c. 2,000 breeding pairs and so new analysis of extinction risk using the updated population estimate and improved demographic data is required. In winter, it occurs in the Balearic Sea and off the north-east Spanish coast with most of the population traditionally concentrated between Valencia and Catalonia from November to February, although recent data suggest that some birds remain in the Atlantic. For instance, in winter 2007/2008 significant numbers (with a peak count of 710 birds) remained off the coast of Brittany (France), perhaps in response to unusual sea surface temperatures (Plestan et al. 2009). Some birds migrate north in summer to seas off the British Isles and the south of the Scandinavian Peninsula (Wynn et al. 2007). Numbers recorded in the traditional post-breeding quarters have declined since the mid-1990, with a corresponding increase in numbers along the coasts of northern France and south-west U.K (Wynn and Yésou 2007, Wynn et al. 2007) (including an exceptional gathering of 4,600 in the Baie de Lannion, Brittany in August 2010) (D. Andrews in litt. 2010).|
Native:Algeria; France; Gibraltar; Ireland; Morocco; Portugal; Spain; United Kingdom
Vagrant:Belgium; Cape Verde; Denmark; Germany; Israel; Italy; Netherlands; Norway; Poland; Sweden; Tunisia
Present - origin uncertain:Albania; Bosnia and Herzegovina; Croatia; Egypt; Faroe Islands; Greece; Libya; Malta; Monaco; Montenegro; Slovenia
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||The breeding population was last estimated in 2009 at 3,193 breeding pairs (CMA 2010). However, winter at-sea surveys along the Iberian Shelf as part of the LIFE project to identify marine Important Bird Areas produced an estimate of 25,000-30,000 individuals (Arcos 2011b), and counts of >18,000 birds past Gibraltar in May-July 2008 were extrapolated to a total of 20,000-25,000 individuals (Arroyo et al. 2011). These data are difficult to reconcile, but a precautionary estimate of 9,000-13,000 mature individuals is considered appropriate (Arcos 2011b, Arcos et al. 2011). This is roughly equivalent to 13,000-20,000 individuals in total.|
|Habitat and Ecology:||It breeds on cliffs and small islets, is very philopatric, and lays only one egg. Adult birds do not commence breeding until their third year (Oro et al. 2004). Breeding takes place between February and June (Ruiz & Martí 2004). When raising young, adult birds form concentrations on the east coast of Spain (Arcos and Oro 2002), where they mostly inhabit the productive continental shelf and associated fronts where high prey concentrations occur around the Ebro Delta (Louzao et al. 2006b). Most birds leave the Mediterranean for a post-breeding moult in the Atlantic coast of southwest Europe, mainly Portugal, northwest Spain and the Bay of Biscay (Ruiz and Martí 2004, Ramírez et al. 2008, Arcos et al. 2009).|
|Major Threat(s):||This is a long-lived species and therefore immediate threats affect adult mortality rates. Adult survival is the main conservation concern, as this is unusually low for a Procellariiform (Oro et al. 2004). In accordance, the main threats identified are predation by introduced carnivores such as cats, martens and genets in the breeding colonies (Arcos and Oro 2004, Ruiz and Martí 2004, Jones et al. 2008, Arcos 2011a), and fisheries by-catch at sea (Arcos 2011a). The species's gregarious behaviour and its close association with fishing boats means that occasional "mass mortality" is likely to occur when long-line boats fish close to flocks (Arcos et al. 2008), Increasing evidence on this has been compiled in the last few years, with events of up to a hundred or more birds caught in a single event, in occasions involving other fishing gear such as purse-seiners (ICES 2008, Louzao et al. 2011). Also due to the congregatory behaviour of the species, acute pollution events, such as oil spills, also pose a very serious threat, as a large number of casualties could result from a spill occurring in a congregation area (Ruiz and Martí 2004, Gutiérrez 2011). Other threats include: the reduction of prey due to fishing overexploitation; a potential reduction in fishing discards (an alternative to the overexploited natural prey) and/or anthropogenic environmental change (Arcos 2011a); habitat degradation and disturbance in the breeding grounds; background pollution (Oro et al. 2008); the development of marine windfarms (Arcos 2011a); and human harvesting (nowadays a relict activity). Predation by peregrine falcons in the breeding colonies has also been recently reported (García 2009, Wynn et al. 2010), though this should be considered as a factor of natural mortality that likely has little influence on the decline of the species. The gradual northward movement of the non-breeding population may be affecting adult survival, and this shift may be due to climate change or alterations in fish distributions as a result of fisheries' activities (Yésou 2003, Wynn and Yésou 2007). The recent demographic decline has not yet decreased the species's genetic variability, and connectivity found among colonies at least does not exacerbate the species's extinction risk (Genovart et al. 2007).|
Conservation Actions Underway
All breeding sites are currently protected as Special Protection Areas (SPAs) under the Natura 2000 network, with the unique exception of the colony of Punta Prima in Formentera, where new information has revealed that the prevailing colony (50 pp.) lays right outside the SPA (and the overlapping Important Bird Area, IBA) designated for this species. However, the management plans for the Balearic SPAs have not been yet implemented. Management plans are therefore limited to colonies covered by other figures of protection, such as the National Park of Cabrera and the Natural Park of Sa Dragonera. Rat eradication campaigns have been conducted at several colonies, including Cabrera archipelago and Dragonera Island, but less effort has been directed at the most concerning colonies where carnivores are present (e.g. Formentera and Menorca). At sea, the Spanish Government has started the process of SPA designation based on the inventory of marine IBAs conducted by SEO/BirdLife, which, once concluded, will provide protection to the main hotspots for the species in Spanish waters. So far, only a few small coastal sites have been designated as SPAs by the regional governments in Spain. Portugal already has an inventory of marine IBAs, but their designation as SPAs is still pending. Finally, France has also proposed a network of SPAs that include hotspots for the species. Management plans for all the marine SPAs are still pending. Action Plans for the species have been published at local, national or international level in 1991, 1999, 2004, and 2005 (Jones et al. 2008). A LIFE project for the species ran from 1991-2001 (Ruiz and Martí 2004), and Spain and Portugal had a joint LIFE project running from 2004-2008 aimed at identifying marine IBAs, including for this species (Ramírez et al. 2008, Arcos et al. 2009). A number of actions are currently being implemented through Species Guardians SEO/BirdLife and SPEA as part of BirdLife's Preventing Extinctions programme. Moreover, research on the species is also being conducted by BirdLife partners in collaboration with several research centres, with funding from EC projects LIFE+ INDEMARES (Spain) and Interreg FAME (Portugal, Spain, France, UK and Ireland). Main initiatives include the assessment of bycatch through questionnaires to fishermen, observers on board fishing vessels and conducting of beached bird surveys; and the identification of hotspots at sea through boat surveys, coastal counts and tracking studies (breeding and non-breeding grounds).
Conservation Actions Proposed
Control and eradicate introduced predators (with particular emphasis on carnivores) in breeding colonies identified to be at risk. Thoroughly study the problem of bycatch by long-line fishing and develop awareness campaigns directed at the fishing sector, in order to mitigate this threat, plus assess and implement the appropriate mitigation measures. Ensure effective protection for nesting sites and marine hotspots, and the implementation of monitoring schemes and management plans. Develop a rapid response plan for a potential oil spill close to main feeding and breeding areas. Raise awareness and stop human exploitation. Study small pelagic fish populations in the western Mediterranean and in the Bay of Biscay to assess extent of over-exploitation and how this affects Balearic Shearwaters. Assess the impact of pollutants and heavy metals on this species. Improve understanding of at-sea distribution, including during the non-breeding season.
|Citation:||BirdLife International 2012. Puffinus mauretanicus. In: IUCN 2012. IUCN Red List of Threatened Species. Version 2012.2. <www.iucnredlist.org>. Downloaded on 20 June 2013.|