Bye-bye blackbird – or in this case myna

P1060024Common Mynas Acrodotheres tristis were introduced to Seychelles in the late 19th century, allegedly to control insect pests, but increasing evidence implicated them in interference, or worse, to some of Seychelles’ endangered endemic birds. Following the eradication of rats and cats from Denis Island in the early 2000s the island was deemed suitable as an environment for establishing populations of Seychelles Warblers, Seychelles Fodies, Seychelles Magpie Robins and Seychelles Paradise Flycatchers. Small numbers of each of these species were duly introduced to Denis to form insurance populations in the event of catastrophic occurrences on the few other islands where these species had managed to survive. However, none of these birds thrived in their new home and Jildou van der Woude, a post-doc from the Netherlands, discovered that a proportion of the Warblers she was studying had severe head injuries and similar injuries were seen to a Flycatcher and a Fody. She obtained evidence that Mynas were to blame.
NGO Green Islands Foundation, which had already contracted WildWings Bird Management to attempt to re-establish a Sooty Tern colony on Denis Island, sought WildWings’ advice on Myna control. In 2010, Chris Feare recruited and trained a volunteer to begin a Myna eradication that began in May. Using further volunteers, again after training from WildWings, the eradication has continued, but with long gaps, into 2015. By late 2014 numbers of Mynas were low and the trapping method that had been so successful was failing to catch remaining birds. GIF’s CEO, Arjan de Groene, managed to recruit a Swedish professional hunter, who managed to shoot the remaining 66 birds within a 3-week period in February-March 2015.
After several months during which no more Mynas have been seen or heard, the island has been declared Myna-free. This eradication is only the second successful Myna eradication involving several hundreds of birds, the first being on Frégate Island, also in Seychelles.
We still have a lot to learn about Myna eradication methodology and evidence to date indicates that different islands may need different techniques to catch the birds. In fact we know very little about the biology of the remarkably dense populations of Mynas that occur on many small tropical islands in all three major oceans. To rectify this, Chris and his Seychelloise friend Christine Larose have begun a ringing programme of Mynas on nearby Bird Island, where there is currently no intention to eradicate them. This aims to provide basic information on the birds’ longevity, fidelity to mate and nesting/feeding areas, and production and survival of young.
Has the eradication on Denis Island relieved the endemic birds of interference from Mynas. Already we can say a firm “yes” and details of this will be posted later.
For a video describing the eradication on Denis Island, visit https://www.youtube.com/watch?v=MFAXJDyWIBs

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s