Justification of Red List category
This species has a very large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km² combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size may be moderately small to large, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
Population justification
The global population is suspected to number fewer than 50,000 mature individuals (Partners in Flight 2022), thus it is here placed in the band 20,000-49,999 mature individuals.
Trend justification
The population is declining as a consequence of the loss, degradation and fragmentation of its habitat, mainly driven by agricultural conversion as well as housing and tourist developments (Cody and Sharpe 2020). Even though it can persist in small patches of scrub and forest habitat, extensive clearance of habitat is causing local declines, e.g. between 2003 and 2008 on Caye Caulker (B. W. Miller in litt. 2008).
Melanoptila glabrirostris occurs on the Yucatán peninsula, in Mexico, Belize, and Guatemala. It is a common to fairly common resident on Cozumel Island and from east Quintana Roo, Mexico, to Ambergris Caye, Belize; common to uncommon on Caye Caulker, Lighthouse Reef and Glover's Reef, Belize. Fieldwork on the north coast of the Sian Ka'an Biosphere Reserve has shown the species to be common there (B. Roldán Clarà in litt. 2008). It is only a scarce and perhaps seasonal or accidental (mainly November-May) visitor over much of the Yucatán peninsula, west to Campeche, Mexico, south to Belize and into Petén, north Guatemala (Phillips 1986, Howell and Webb 1995; B. W. Miller in litt. 2007, 2008). At least c.40 small breeding colonies have been located in the interior of the Yucatán peninsula, with two composed of at least 100 individuals (including 31 in Yucatán - for example in the Hunucmá area, Izamal and Dzonot Carretero, 6 in Quintana Roo and 2 in Campeche) (B. McKinnon de Montes in litt. 2008, 2011, 2016). There are no records from Honduras since the type-specimen was purportedly collected at Omoa in 1855 or 1856, leading to speculation that the specimen may have been mislabelled (Ridgely and Gwynne 1989).
It inhabits humid to semi-arid scrub, scrubby woodland and forest edge, including seasonally flooded and deciduous forest and secondary growth (P. A. Wood in litt. 2008), but also mangrove and littoral forest on cays (E. McRae in litt. 2008). Breeding largely lasts from April until mid-August with nests typically built in Thrinax radiata palm and Pithecellobium keyense bush and containing clutches of between 2-3 eggs (Roldán-Clarà et al. 2018).
Tourism and housing development and conversion to coconut plantations are causing habitat loss and fragmentation in the core of its range on the Quintana Roo coast, Cozumel, and the cays in Belize (Miller and Miller 1991, Stattersfield et al. 1998, E. McRae in litt. 2008, C. J. Sharpe in litt. 2011). It is also potentially threatened by periodic hurricanes, particularly if their frequency and intensity increase; however, impacts from hurricanes have so far not been serious and the species persists in secondary habitats (P. A. Wood in litt. 2008, R. Curry in litt. 2008). Nest predation by Great-tailed Grackle, Quiscalus mexicanus, may be an additional threat to this species (Roldán-Clarà et al. 2013).
Conservation Actions Underway
The species is found within the Shipstern Nature Reserve, Corozal, Belize (Bonmatin et al. 2019). The Siwa Ban Reserve was designated in 1998 expressly to protect the population on Caye Caulker, but it is unclear whether this has provided adequate protection (B. W. Miller in litt. 2000). Belize Caye Development policy grants protection to littoral forest; however, in reality this may not be enforced (E. McRae in litt. 2008) and a considerable area of mangrove has been cleared on Ambergris Caye since the mid-1990s (C. J. Sharpe in litt. 2011). Although it is common in the Sian Ka'an Biosphere Reserve, all of the coastal land is private and house construction is permitted in most areas (B. Roldán Clarà in litt. 2008). The species is on the watch list as part of the State of North America's Birds (North American Bird Conservation Initiative 2016).
Conservation Actions Proposed
Accurately quantify the population size. Investigate where the Yucatan birds go in winter to see if they are a distinct population from those found in the Quintana Roo coastal zone or are from the same population, in which case they definitely need maximum protection (B. MacKinnon de Montes in litt. 2016). Research the species' tolerance of habitat degradation. Monitor the population trend. Monitor rates of habitat loss.
Adequately protect the important population on Cozumel Island. Protect remaining habitat. Consider habitat restoration. Enforce the protection afforded to the species by the Siwa Ban Reserve.
Text account compilers
Everest, J., Hermes, C.
Contributors
Capper, D., Clay, R.P., Curry, R., LaPergola, J., MacKinnon de Montes, B., Mahood, S., McRae, E., Miller, B.W., O'Brien, A., Roldán Clarà, B., Sharpe, C J, Taylor, J., Westrip, J.R.S. & Wood, P.A.
Recommended citation
BirdLife International (2024) Species factsheet: Black Catbird Melanoptila glabrirostris. Downloaded from
https://datazone.birdlife.org/species/factsheet/black-catbird-melanoptila-glabrirostris on 23/12/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from
https://datazone.birdlife.org/species/search on 23/12/2024.