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MSc Study opportunity:  Assessing the impacts of boat-based tourism on waterbirds at De Hoop Vlei


Applications are invited for the above study opportunity at the Percy FitzPatrick Institute, a world-renowned, national Centre of Excellence (CoE) in ornithological research with a strong emphasis on postgraduate studies.

We are looking for a dynamic, enthusiastic student to undertake a study of the impacts of boat-based tourism on waterbirds. The study will take place on De Hoop Vlei, a RAMSAR wetland in the De Hoop Nature Reserve. Comparative data will be collected from other wetlands in the Western Cape. Fieldwork will commence in 2015 and last approximately 15 months, with accommodation available within De Hoop Reserve.

Funding is secured for an annual R90 000 bursary for two years and adequate project running costs

Requirements:

·      A strong BSc Honours degree

·      An interest in environmental impacts

·      A desire to spend time in the field

·      Drivers licence

·      Ability to swim

Recommendations:

·      Ability to identify waterbirds

·      Experience with canoes and small boats

Further details of the project are available on request. Please send a letter of motivation and a CV, including contact details for at least three referees, to Prof. Peter Ryan (pryan31@gmail.com).  For enquiries, call +27 21 650-3290/1.

Closing date: January 15, 2015

A Murder of crows?  Press release on crow study conducted by researchers at the FitzPatrick Institute



Photos:  Peter Ryan 

They steal, raid nests, and keep the company of witches. But the unpopular crow may not be as big a menace as people think. A new study has found that crows – along with their avian cousins the magpie and the raven – have surprisingly little impact on the abundance of other bird species. Collectively known as corvids, these birds are in fact being menaced by mankind in the mistaken belief that removing them is good for conservation.

The new study was led by researchers at the University of Cape Town and published this week in the leading ornithological journal Ibis1. It found that in the vast majority of cases (82 percent), corvids had no impact at all on their potential prey species. "Many nature lovers have been distressed to witness a crow or magpie raiding the nests of their beloved garden songbirds, stealing their eggs or eating their defenceless chicks," said study co-author Dr Arjun Amar2 from the Percy FitzPatrick Institute of Ornithology3. "Although this predation is entirely natural, these observations can be upsetting to witness and often leave people wondering if these predators might be reducing bird numbers."

“However, our global review suggests that we should be cautious before jumping to conclusions over the impacts these species may have. Just because a predator eats something occasionally does not always mean that they have an impact,” Dr Amar said. The study, the first of its kind, reviewed all published evidence on whether predation by corvids actually reduces the overall breeding performance of birds or, more importantly from a conservation perspective, reduces their numbers. Data were collated from 42 studies of corvid predation conducted across the globe over the last sixty years.
Not only were corvids unlikely to have any impact on their potential prey species, if there was an impact it most often affected the breeding success of the prey species rather than their subsequent numbers. Half of cases found that corvids reduced breeding success whereas less than 10% of cases found that they reduced prey numbers in the long term.

“These results have big implications for the likely benefits of corvid control,” Dr Amar said. “They suggest that killing corvids will be of most benefit to those interested in gamebird shooting rather than conservationists.” He added: “Bird hunters are usually most interested in increasing numbers of birds available to shoot immediately after the breeding season and this appears to be where corvids have most impact”. “Conservationists on the other hand, are usually interested in increasing a species population size and our results suggest that only in a very few cases did corvids have an influence on this aspect of their prey,” Dr Amar said.

The review analysed the impact of six corvid species on a variety of prey species including gamebirds, songbirds, waders, herons, cranes, sea birds, waterfowl and raptors. The 42 studies incorporated into the review included 326 cases of corvid – bird prey interaction Most of the data stemmed from field research in the UK, France and the United States. The impacts were determined partly by comparing bird counts before and after corvids were either removed or their numbers reduced.

The review also found large differences between the impacts of crows, historically considered the most 'cunning' corvid, and magpies which are sometimes killed by home owners hoping to protect songbirds in their gardens. Crow species were six times more likely to have an impact on bird prey species than Magpies.  Mistaken assumptions about corvid predation were possibly explained by the birds' diurnal nature and the fact that they are conspicuous nest predators: “Their importance in prey population regulation is often assumed prior to any assessment of the evidence,” the study warned.

Chrissie Madden4, the lead author on the paper, hoped that the review would challenge the perception that all corvids were bad, thereby preventing needless killing: “Our results suggest that this is a mistaken belief and that generally speaking people would be wasting their time killing corvids to increase bird numbers”. “Overall therefore, our study points to the fact that we are often too quick to jump to the conclusion that crows and magpies may be the cause of bird population declines,” she said.

For further information and to arrange an interview, please contact:
Dr Arjun Amar – arjun.amar@uct.ac.za, Phone: +27-(0)21-6503304, Cell:+27-(0)79-5855603

Editor's notes:
1. The Ibis is a peer reviewed scientific journal published by the British Ornithologists’ Union. It has been published since 1859 and is one of the highest ranked international Ornithological journals in the world. http://www.bou.org.uk/ibis/
2. Dr Arjun Amar is a Senior Lecturer at the Percy FitzPatrick Institute and was the lead supervisor of this research project. Dr Amar has previously worked for both the Royal Society for the Protection of Birds (UK BirdLife partner), the Game and Wildlife Conservation Trust (UK NGO), and the US Fish and Wildlife Service, where he worked on a critically endangered species of crow (the Mariana Crow on the Pacific island of Rota, CNMI). http://www.fitzpatrick.uct.ac.za/docs/arjun.html
3. The Percy FitzPatrick Institute of African Ornithology is a research institute situated in the Biological Sciences Department of Cape Town University. It is one of the world’s leading ornithological research institutes and is a South African Department of Science and Technology-National Research Foundation Centre of Excellence.
4. Chrissie Madden is the lead author of the paper. The research was undertaken as part of her Conservation Biology Masters research at the University of Cape Town.

The full paper is freely available via open access.The full reference for the paper is: Madden, C.F., Arroyo, B. & Amar, A. (in press) A review of the impact of corvids on bird productivity and abundance, Ibis. doi: 10.1111/ibi.12223

Full free access: http://onlinelibrary.wiley.com/doi/10.1111/ibi.12223/abstract 

Please report any sightings of ringed Swift Terns


Swift Terns are one of the few locally-breeding seabirds whose numbers are increasing., To help understand the main factors driving the positive trend of this species, a team of researchers from the Percy FitzPatrick Institute and the Animal Demography Unit at the University of Cape Town marked 500 Swift Tern chicks from Robben Island in April 2013 and 2014 with metal and individually engraved colour rings. In 2013, members of the public reported how these birds dispersed, providing information on the fledging success, survival and dispersal of juvenile Swift Terns, which were re-sighted from Namibia to the Eastern Cape. Gathering dispersal records is a time consuming but important task that relies on assistance from volunteers across southern Africa.

Rings in 2014 are orange and yellow (with black text) and green and blue (with white text), and are engraved with an “A” followed by a letter and a number (e.g. AU2). Rings from 2013 are yellow and white (with black text) and green and blue (with white text), and bear a code of one letter and one number (e.g. U2).  The majority of the colour rings are top-down and all are on the right leg.

If you see any ringed birds please record their location as accurately as possible (ideally GPS), the date and time of sighting, ring colour, letters on the ring (if legible) and age class (juvenile or immature). If a bird is found dead, please also record the number of the metal ring. Send the information to Davide Gaglio at swift.terns@gmail.com

Thanks for your help!

Last modified: 2014/12/17
Copyright: Percy FitzPatrick Institute of African Ornithology 2014
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