Procellaria conspicillata
| Kingdom |
Phylum |
Class |
Order |
Family |
| ANIMALIA |
CHORDATA |
AVES |
PROCELLARIIFORMES |
PROCELLARIIDAE |
| Scientific Name: |
Procellaria conspicillata |
| Species Authority: |
Gould, 1844 |
Common Name/s:
| English |
– |
Spectacled Petrel |
|
| Taxonomic Notes: |
Procellaria aequinoctialis (Sibley and Monroe 1990, 1993) has been split into P. aequinoctialis and P. conspicillata following Brooke (2004).
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Assessment Information
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| Red List Category & Criteria: |
Vulnerable
D2
ver 3.1
|
| Year Published: |
2012 |
| Assessor/s: |
BirdLife International |
| Reviewer/s: |
Butchart, S. & Symes, A. |
| Contributor/s: |
Bugoni, L., Cooper, J., Croxall, J., Favero, M., Hilton, G. & Ryan, P. |
Justification:
This species is listed as Vulnerable because, despite apparent population increases, significant numbers are caught as bycatch in longline fisheries, and, owing to its very small breeding range, it is highly susceptible to stochastic events and human activities.
|
| History: |
| 2010 |
– |
Vulnerable
|
| 2008 |
– |
Vulnerable
|
| 2007 |
– |
Vulnerable
|
| 2005 |
– |
Critically Endangered
|
| 2004 |
– |
Critically Endangered
|
| 2000 |
– |
Critically Endangered
|
| 1994 |
– |
Not Recognized
|
| 1988 |
– |
Not Recognized
|
|
Geographic Range
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| Range Description: |
Procellaria conspicillata is essentially confined to the South Atlantic Ocean north of the South Polar Front, predominantly between 25-41°S (ACAP 2009). It breeds only on the high western plateau of Inaccessible Island, Tristan da Cunha, St Helena (to UK). In 1949-1950, the population was estimated to be at least 100 pairs, probably considerably more (Rowan et al. 1951). In 1982-1983, it was estimated at c.1,000 pairs (Fraser et al. 1988, Ryan 1998). In 1999, 6,000-7,500 burrows were counted (c.60% occupied), but failures prior to this stage and the presence of non-breeders confound an accurate population estimate (Ryan and Moloney 2000). A repeat survey in 2004 counted 11,000-12,000 burrows, with 14,400 counted in 2009-2010 (Ryan et al. 2011). Assuming an occupancy of 90% this suggests a breeding population of 20,000 individuals (Ryan et al. 2006). An extrapolation from snapshot censuses conducted in waters off Brazil in 1997-1999 suggested a total population of 38,000 ± 7,000 (Leandro Bugoni in litt. 2006). This population increase over time is thought to have been initiated by the eradication of pigs from Inaccessible Island. Between 1999-2004, the species may have increased by up to 45% (Ryan et al. 2006) but the toll taken by bycatch in longline fisheries is poorly understood. Most birds disperse to the waters off southern Brazil outside the breeding season, with small numbers recorded off the west coast of southern Africa. In the 19th century, it may have occurred throughout the Indian Ocean, possibly breeding at Amsterdam Island (French Southern Territories), and was also collected at sea off Australia (Enticott and O'Connell 1985, Ryan 1998).
|
| Countries: |
Native: Argentina; Brazil; Namibia; Saint Helena, Ascension and Tristan da Cunha; South Africa; Uruguay
Vagrant: Angola (Angola); Australia
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| Range Map: |
Click here to open the map viewer and explore range. |
Population
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| Population: |
14,400 nesting burrows were counted on Inaccessible Island in 2009-2010 (Ryan et al. 2011). Assuming 90% occupancy, this equates to a breeding population of approximately 20,000 birds. The population is estimated at around 38,000; 7,000 individuals were present at sea off Brazil based on survey data from 1997-1999 (L. Bugoni in litt. 2006).
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| Population Trend: |
Increasing
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Habitat and Ecology
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| Habitat and Ecology: |
Behaviour Procellaria conspicillata breeds annually and is active in colonies from September to March. Breeding phenology has not been well studied, but egg-laying commences in October, with hatching in December and the chicks fledge in March (ACAP 2009). Habitat Breeding It breeds in wet heath above 380 m (P. G. Ryan in litt. 1999). Burrows are along the banks of river valleys (Fraser et al. 1988) and in adjacent marshy areas (P. G. Ryan in litt. 2000). Diet It feeds on cephalopods, decapod crustaceans and small fish (Hagen 1952). A total of 121 food items (five fish and 116 cephalopods) were found in the diet of seven longline-caught birds off the coast of Brazil (Colabuono and Vooren 2007).
|
| Systems: |
Terrestrial; Marine |
| Major Threat(s): |
Feral pigs may have caused the apparent extirpation of Procellaria petrels from Amsterdam Island and may have had an impact on Inaccessible throughout most of the 19th and early 20th centuries (Fraser et al. 1988, Ryan 1998). Southern Skua Catharacta antarctica is a natural predator, particularly of fledglings (P. G. Ryan in litt. 1999), and there is a permanent risk of colonisation by mammalian predators, particularly black rat Rattus rattus from Tristan. The greatest threat comes from interactions with longline fisheries, given estimates of more than 200 killed annually off southern Brazil during the late 1980s and early 1990s (Ryan 1998), revised to c.700 annually more recently (Olmos et al. 2000). However, according to a report by Projeto Albatroz observers recorded zero mortalities of spectacled petrel during nine trips on Brazilian longline vessels in 2005, and though it was the most common seabird off longline vessels in one study, its capture rate was one of the lowest (Bugoni et al. 2008). There may be high overlap in the distribution of this species and longline fishing effort off southern Brazil, and this is supported by recent satellite telemetry (L. Bugoni in litt. 2009).
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Conservation Actions
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| Conservation Actions: |
Conservation Actions Underway
CMS Appendix II and ACAP Annex 1. Inaccessible is a nature reserve and, although Tristan Islanders retain the right to collect driftwood and guano, other access is restricted (Cooper et al. 1995). A repeat of the 1999 breeding bird census on Inaccessible was conducted in 2004. Ongoing studies will attempt to quantify the current level of bycatch in fisheries off southern Brazil.
Conservation Actions Proposed
Conduct repeat surveys of the breeding population (Ryan 1998). Promote adoption of best-practice mitigation measures in all fisheries within the species's range, including via intergovernmental mechanisms such as FAO, ACAP and Regional Fisheries Management Organisations including the International Commission for the Conservation of Atlantic Tunas (ICCAT). Minimise the risk of colonisation by introduced species through strict controls of visits and promoting awareness of dangers of inter-island transfers (P. G. Ryan in litt. 1999). Nominate Inaccessible for World Heritage Site status (J. Cooper in litt. 1999). Investigate the possibility that the birds may nest at other sites than Inaccessible, particularly Tristan da Cunha. Instigate demographic studies. Investigate at-sea distribution and interaction with longline fisheries.
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