Source: Charles Darwin Foundation
Controlling the flies to save rare birds from extinction
In the nests of Darwin's finches and other Galapagos birds lurks a deadly intruder. Feeding on the blood of the nestlings, the larvae of an introduced fly, Philornis downsi, cause mortality of up to 76%. Although in Galapagos since 1964, P. downsi wasn't discovered in nests until 1997. CDF volunteer entomologist and Fulbright scholar, Adair Muth, is trying to find a way to trap adult flies using attractants such as banana, urine and stale beer but the flies seem to like a mix of sugar and dry milk powder the best. The most efficient methods will be used in priority areas during the next breeding season, in an effort to increase reproductive success of rare birds such as the mangrove finch.
Muth's research is also providing valuable clues to help identify control methods such as sterile insect techniques as a long-term solution to stop the spiral toward extinction of the rarest birds. The challenge is to find a way to rear larvae and adults on site at the research station using samples collected from active nests in Puerto Ayora. After a successful collection trip an excited Muth said "I caught a live female which laid eggs all over the inside of the collection tube! Until that moment we didn't know if P. downsi laid live larvae or eggs. They lay eggs!"
Previous CDF studies on P. downsi showed extensive distribution in the archipelago: 11 of 13 islands sampled. Affected birds include finches, mockingbirds and flycatchers. These birds, especially the famed Darwin's finches, show just how quickly species can be harmed when man intrudes upon Nature.
Increased air traffic - invasive species get new wings
The rising number of planes traveling to Galapagos is outstripping the ability of the quarantine programme to prevent the introduction of invasive species. Based on recent studies funded by the Global Environmental Facility, CDF urgently recommend that the Galapagos Quarantine and Inspection System (SICGAL) be strengthened and that procedures for disinfection of planes be improved and strictly enforced.
Serving the needs of unprecedented tourism and population growth, flights to the islands have increased by 193% since 2001. There are multiple daily flights from mainland Ecuador. Private planes have arrived directly from other countries and could bring new pests and diseases such as West Nile virus. Other private planes leave from airports on the Ecuadorian mainland where no or only limited inspection is possible due to insufficient resources. Said Charlotte Causton, CDF's head of invertebrate research, "SICGAL inspectors have been reduced by 20% when the number of passengers, luggage and freight has more than doubled, making efficient inspection impossible."
No quarantine system can be 100% effective but the risk can be significantly reduced if air access to the islands is limited to specific routes where strict quarantine measures can be taken. Says David Cruz, CDF's technical advisor to SICGAL, "Improving the ability of SICGAL to manage increased air traffic must be a top priority if pests are to be stopped entering the islands. The unique species, the very reason why people come to Galapagos, are at great risk."
Introduced rats - is eradication possible?
The black rat, Rattus rattus, and the common house mouse, Mus musculus, are two of the most invasive and destructive invasive species to have arrived in Galapagos since the discovery of the islands in 1535. During a workshop arranged by the CDF and the Galapagos National Park Service, local management authorities, scientists and international experts on invasive species control discussed how these rodents could be eradicated.
According to Linda Cayot, the workshop coordinator and CDF researcher, "The combination of expertise at this workshop has already created an exciting plan for Pinzon Island which will provide a testing ground for the eradication of [introduced] rodents from the entire archipelago."
While representing a huge challenge for scientists and managers, the plan for Pinzon Island is strategically designed to look to the future, when the knowledge and technology exist to eradicate introduced rodents from the larger, more complex islands. Introduced rodents are having major - and potentially irreversible - detrimental effects on biodiversity both in the Galapagos and elsewhere. Together the CDF and GNPS aim to develop a state-of-the-art rodent eradication programme that will serve as a model for other island ecosystems worldwide.
CDF would like to thank the UK-based Galapagos Conservation Trust and Lindblad Expedition's Galapagos Conservation Fund for their financial support for the workshop.
Students get a green "thumbs up" for native plant project
Twenty students from the Santa Cruz Island branch of Central University and supervised by CDF botanists prepared hundreds of native plants for the Miguel Cifuentes Memorial Garden, opened on June 5th - World Environment Day - by Santa Cruz Island Mayor Leopoldo Buchelli. The students worked for three months in the CDF nurseries in Bellavista and Puerto Ayora, collecting and planting seeds and seedlings and tending the plants. Their goal was to "green" an abandoned space in front of the new Environmental Management offices of the Santa Cruz municipality. "We have created a place where people can relax and enjoy the unique flora of the island," said Dario Morales, student coordinator. This CDF project, supported by the Nordic Friends of Galapagos, showcases how to create beautiful gardens that are both unique and present no threat to biodiversity.
"By encouraging people to plant native gardens we hope to curb the spread of invasive ornamentals," said CDF introduced plants specialist, Rachel Atkinson. "'Out of place' decorative plants can affect agriculture as well as biodiversity, as their control requires significant financial investment."
The garden honors Miguel Cifuentes, ex-mayor of Santa Cruz and ex-CDF president, who was a role model for many young Galapagos people and a renowned conservation expert and visionary. It is fitting that with his passing away in April the new native garden will be a tribute to his passion for all things Galapagos and his belief in people working together in harmony with nature.
For CDF's full news bulletin, visit e-Newsletter: Charles Darwin Foundation.
