When a team of researchers travelled around Ghana to conduct a Grey Parrot (Psittacus erithacus) census, they encountered a very pronounced generation gap. “The older people we surveyed remember the Grey Parrot well”, says Stuart Marsden, Professor of Conservation Ecology at Manchester Metropolitan University, and one of the leaders of the study. “The species used to roost in large trees in their thousands. They remember them being common sights around the villages, as pests who would eat their fruit. Living alongside the Grey Parrot was simply a fixture of being a Ghanaian.” But times change. “What’s worrying is how few of the young people in Ghana we interviewed even knew or cared about the species”, says Marsden. “Once you get to a certain age, people haven’t even heard of the Grey Parrot. It echoes the Java Sparrow situation in Java. The Grey Parrot should be Ghana’s national bird. Instead, it has all but disappeared.” While many young Ghanaians may not have seen a Grey Parrot, the chances are good that if you’ve ever walked into a pet store, you have. You might even have held one on your arm – or held a conversation with it. The Grey Parrot is an intelligent, gregarious bird, and an excellent mimic of the human voice. These qualities make the Grey an endearing companion; it has become one of the most popular pet birds in Europe, North America and the Middle East. However, this popularity has come at a terrible price. Every year, trappers pluck tens of thousands of Greys from Africa’s rainforests to meet international demand, a practice that occurs throughout its range and has been ongoing for decades. The exact method used to capture the bird varies from region to region, but commonly involves trappers climbing the tall trees it prefers to nest in and taking fledglings directly from the nest. Elsewhere, trappers take advantage of the bird’s social nature, throwing nets over them when they congregate at drinking or mineral lick sites.
The effect these wide scale captures are having on the continent’s Grey Parrot population is easy to imagine, but difficult to quantify. Firstly, as one of the world’s most illegally trafficked birds, is difficult to know exactly how many birds are being extracted from the wild each year. The Convention on International Trade in Endangered Species of Wild Flora and Fauna (CITES) reported that imports from range countries totalled 847,525 between 1980-2014, but the true figure is likely in excess of a million. Even official figures don’t factor in that wild-caught Grey Parrots, contrary to their popular image as hand-tame companion birds, are extremely sensitive to being handled; a huge number of captured birds die from stress. As an example, in the late 1990s and early 2000s Cameroon reported an annual quota of 10,000 birds captured in the wild in that country alone. However, research estimates that as many as 90% of birds caught perished before they reached the airport. This would mean the true figure of Greys captured in Cameroon each year was closer to 100,000.
There is another obstacle to determining the threat status of the Grey Parrot. While it’s relatively easy to track the population trend of a bird that is endemic to a small area or island, the Grey Parrot’s range spans nearly three million km2, from Côte d’Ivoire and Ghana in West Africa, to the Congo Basin, and east to Uganda and Kenya. The species has a very variable population size across its range, making it difficult to quantify how much danger it truly is in. “In Ghana, the decline in Grey Parrots has been devastating. But in other parts, like Gabon, it probably is still quite numerous”, says Marsden. “The further west away from the heart of the Congo Basin, the bigger the problems seem to be.” Compounding the issue, very little is known about the Grey Parrot’s historical population sizes. Although Grey Parrots have been harvested from Africa since the late 19th Century, and there are local anecdotes that tell of their noticable decline, without tangible, baseline historical data to compare with current population trends, it becomes difficult properly to pin down the true extent of the problem. However, in the quest to determine the Grey Parrot’s status, Marsden got lucky. “We found a report by Gottlieb Dändliker, a consultant for CITES, who put together a fantastic report about the trade and ecology of the species in Ghana in the early 1990s. It included metrics which we could repeat today – such as roost surveys and encounter rates.”
The discovery of this unpublished, but technically meticulous report provided a unique opportunity to measure the degree of decline in Ghana over the past 20-25 years. “This kind of data is something that’s absent from so many species in the world”, says Marsden. “If more people set up these databases for common birds today, we would thank them so much in 50 years’ time.” Dändliker travelled around Ghana in 24 days, between December 1991 and January 1992, identifying 60 Grey Parrot roosts or roost areas, some of which contained hundreds of birds.
This survey was conducted at a time when Ghana boasted an estimated Grey Parrot population of 30,000-80,000 birds – a figure that was likely already a shadow of the numbers seen just a few decades before, when the parrot was abundant. The follow-up project, which was co-supervised by Marsden and Dr Nathaniel Annorbah, both of Manchester Metropolitan University, and BirdLife International’s Dr Nigel Collar, attempted to replicate Dändliker’s roost counts as closely as possible.
Of the 60, the team were able to visit 42 of the roost areas identified by Dändliker. Their findings, or lack thereof, told the story of a dramatic decline. No active roosts were found, and locations that in 1992 hosted roosts of 700-1,200 Grey the decline of Grey Parrots in Ghana is certainly more than 90%, and may be as high as 99%.
The data provide, for the first time, quantitative evidence of the devastating effect decades of trapping and trade have had on populations of the Grey Parrot. Armed with this information, the Red List team were able to determine that the declines met the threshold required for the species to be uplisted to Endangered. The Timneh Parrot Psittacus timneh, a newly recognised species that until 2012 was considered a subspecies of the Grey, has also been uplisted to Endangered, as it faces the same threats. Because it has a much smaller range, and is concentrated in countries such as Sierra Leone and Liberia, that have been ravaged by war and Ebola, Marsden feels the Timneh should be the focus of future studies. “I would put the Timneh far above the Grey in terms of extinction risk”, says Marsden. “It’s really only reasonably common in a handful of places, such as the Gola Forest in Liberia. We need to assess which areas have, or don’t have viable populations.”
The Gola Forest’s newly declared status as a National Park should do much to secure the future of this Timneh stronghold. But elsewhere, habitat loss is another pressure to the Grey’s survival. Marsden notes that the Ghana he visited had experienced noticeable landscape changes from the one Dändliker described in 1992. “With your normal threatened bird, the first port of call is usually land use change”, says Marsden. “But as soon as trade comes into it, it’s easy to forget a little bit about the concurrent changes to habitat. Yes, the trade has been devastating. But at the same time, a lot of forest coverage has completely disappeared.”
Greys prefer tall trees for roosting and nesting, and many of these have disappeared from Ghana altogether. The cause is a mix of forestry policy and a law that says that big trees remain owned by the government, even if on privately owned lands. So farmers have been cutting down big trees so logging companies won’t arrive to do damage. “Even if there had been no trade, tree loss would have caused a decline anyway”, says Marsden. “But it’s a complex situation. The problems the species face seem to be different in each country.” In Kenya for example, the species is now absent from many forests where it was once locally common. Kakamega Forest, which now harbours the country’s largest population, likely has less than ten mature Greys remaining. The species is faring better in the Congo Basin, but with thousands of birds being trapped annually in the region, the Grey’s presence could eventually fade there, too. Already, the large flocks that previously occurred around DR Congo’s capital, Kinshasa are now reportedly gone.
In response, CITES member states have now voted to increase the protection of both the Grey and the Timneh to the highest possible level, Appendix 1, which outlaws all international trade. However, Marsden feels this alone will not allow the Grey to bounce back: “We can’t just say that because CITES has banned trade, everything’s going to be okay. It’s not – trade control is far from effective in many parts of its range.”
In response, the Ghana Wildlife Society (GWS, BirdLife Partner) is looking to engage with authorities to protect their remaining Grey population. “Our intention is to work on preventing any underhand trade, get access to the dealers, and engage communities to conserve the remaining roosts” says Japheth Roberts, Research Coordinator, GWS.
For now, conservation groups must continue to work to conserve these species’ remaining strongholds in Africa’s countryside. However, Marsden ends our discussion with a surprising tale of the Grey’s resilience: the species has now started moving into busy cities such as Kampala and Accra. It would be ironic, and perhaps a little tragic, if future generations of Ghanaians knew the Grey only as an urban bird.
Source: Birdlife, 8 Dec 2016
http://www.birdlife.org/worldwide/news/grey-parrot-fading-africas-rainf…
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