The wildlife of the Galapagos Islands is the most uniquely adapted in the world. It was in this archipelago, off the coast of South America, that naturalist Charles Darwin based his research that subsequently became his ground-breaking “Theory of Evolution”.
Today the archipelago is a popular place for eco-tourism, with a wildlife cruise in Galapagos often sitting at the very top of a nature lover’s wish list. But in spite of â€“ and, in some cases, because of â€“ the islandsâ€™ remote geographic position, many of the species face serious threats to their survival, and some are already extinct.
The land birds of the islands are one group whose number are in decline, the most notable of which are Darwin’s Finches (which are actually 15 separate species) â€“ so named for their “light bulb” role in Darwin’s theory of natural selection.
Saving the Land Birds
The Charles Darwin Research Institute (CDRI) on Santa Cruz, is a site thatâ€™s on the itinerary of every wildlife cruise in Galapagos. Their valuable ongoing work is essential to the preservation of the archipelago’s wildlife, and one of their many projects is focused on controlling a parasitic fly that is endangering Darwin’s Finches.
Philornis downsi is an introduced species, whose larvae live and feed on the hatchlings of the finches, causing large numbers of them to die in the nest. This ectoparasite is also believed to be responsible for the decline in other avian species.
The Philornis Project
The research carried out by the CDRI began with attempts to rear the larvae of Philornis downsi in the laboratory, without the aid of an avian host. This difficult task was achieved for the first time by a dedicated undergraduate thesis student, although raising the fly in the large numbers required for research purposes continued to pose a problem.
Researchers from the CDRI travelled to Panama to observe the work of the Screwworm Barrier Maintenance Programme, where millions of “sterile” flies are produced on a regular basis to aid in the project to eradicate the invasive screwworm. The researchers were able to transfer what they gleaned from this highly successful project and apply it to their own with very positive results.
Although the CDRIâ€™s flies are being bred in greater numbers due to the teamâ€™s achievement of improving some of the Panama projectâ€™s techniques, getting the flies to mate on a regular basis is still proving a challenge. However, there is a large and dedicated team working on the project, and they’re confident that theyâ€™ll reach a solution.
Learning more about the biology of the fly is vital to the next step in the programme to develop successful methods to control its numbers. Once a regular breeding programme is established, research into effectively managing the fly will provide a massive step forward in the conservation of the archipelago’s land birds.
Small Projects Making a Big Difference
For anyone planning a wildlife cruise in Galapagos, understanding the vital work of the CDRI will offer a greater insight into this magnificent part of the world and the challenges it faces. The ongoing Philornis project is just one example of how seemingly small conservation projects have the potential to make a huge difference to the ecology of the islands.
Marissa Ellis-Snow is a freelance nature writer with a special interest in the Galapagos Islands. For those interested in a wildlife cruise in Galapagos, Marissa recommends the itineraries organised by Naturetrek, which have brought her unforgettable sightings of a wide range of species in one of the most spectacular regions on Earth