Friday, 21 March 2014

Searching for Grey Parrots in Ghana

Posted by Nathaniel Annorbah & Stuart Marsden


In his study, Nat has to cover a huge study area of
60,000 sq. km across the South West of the country.

The aim of the PhD research is to assess the historic and current distribution, abundance and ecology of the Grey Parrot Psittacus erithacus in Ghana in order to make informed predictions about the sustainability of trade and land-use changes. Relevant data on other frugivorous birds such as hornbills and pigeons are being collected at the same time. Despite its large geographical distribution, the Grey Parrot population is suspected to be suffering a rapid decline because the extent of the annual harvest for international trade, and the high rate of ongoing habitat loss. The species is listed as Vulnerable in the (BirdLife International 2014).

Nat has already conducted surveys for Grey Parrots and other fruit-eating birds between April 2012 and March 2013, and he is now again in Ghana to continue his work on greys. His study area is huge - about 60,000 sq. km, comprising a mosaic of inhabited, cultivated and forested areas in south-western Ghana, the stronghold of grey parrots in the country.


Selective logging in forest reserves takes the largest trees. Logging company staff tell us that the huge trees they harvest often have 'nail ladders' allowing trappers to climb to the parrot nests (Photo: Stuart Marsden).



The study area was partitioned into a grid of 10 x 10 sq. km cells. A random sample of around 50 cells has been selected for surveys. 3-5 days are spent in each cell trying to find evidence for the presence of parrots and other frugivores. These ‘presence’ points will form the basis of a MAXENT analysis of current parrot distribution. Interviews were also conducted in the cells to obtain information about local people’s knowledge of the Grey Parrot, but also to record the socio-economic aspects of the its trade. Particularly important is the information on the historic presence of grey parrots in each cell – these points will form the ‘historic’ presence points for a MAXENT analysis of the past distribution.


Nat interviews local hunter-farmers to better understand the historic range of the Grey Parrot in SW Ghana (Photo: Stuart Marsden)

A great part of fieldwork was to locate roosts of Grey Parrots and to count birds to estimate roost population sizes. G. Dändliker (1992), a CITES consultant, did a survey of parrot roosts in Ghana in the early 1990s – some of these roosts contained hundreds of birds. It is our aim to visit as many of these roosts as possible to see how they have changed over in the subsequent 20 years. Locating roosts needs accurate information provided by trappers or local knowledge in general and a lot of legwork.

Fieldwork conditions: rain can soon transform roads in rivers (Photo: Nat Annorbah).




Fieldwork in Ghana has not been easy. Torrential rain makes ‘road’ conditions atrocious, the 4WD has taken a battering, electricity is scarce, and illnesses such as malaria are a real concern. Even local elections made things difficult in places.




A total of just 101 parrots were encountered during the first year’s survey. Parrots were recorded in just nine of the 31 surveyed sites surveyed  and not one wild grey parrot has so far been recorded in this year’s survey. Grey Parrots were present in only three of twelve roost sites revisited from the 1992 study and all 16 of Dändliker’s roosts visited so far this year have been ‘empty’. We will soon post on what looks like a collapse of the grey parrot population right across the country.


Excessive parrot trade has surely had a big hand in the disappearance of Grey Parrots from Ghana. Despite being incredibly rare in the wild, a few can still be found for sale.

References

BirdLife International. 2014. Species factsheet: Psittacus erithacus. Downloaded from http://www.birdlife.org on 14/02/2014.

Dändliker, G. 1992. The Grey Parrot in Ghana: a population survey, a contribution to the biology of the species, a study of its commercial exploitation and management recommendations. A report on CITES Project S-30.  Unpublished report to CITES.


Nat's PhD is funded by





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