Finches, finches and then some

November 9, 2017 | Categorized in: | By: Deborah Kilcollins

After just a bit of research, it is clear there is so much we do not know about the world’s birds and how they are doing. The statistics seem to vary widely. Some estimates say there are roughly between 100 and 400 billion birds in the world. Yet, we do not even know exactly how many species that encompasses. The number of bird species is usually thought to range between 9,000 to 10,000, but some scientists believe that number may be as high as 18,000 different species… or more. We simply do not know.

The International Union for the Conservation of Nature Red List, considered the authority on the status of the world’s species, now includes 1,227 bird species (12 percent of known birds) as threatened with extinction – 192 of those critically endangered.

Included in the endangered group are several finch species including yellow-headed brush finch, black-spectacled brush finch, pale-headed brush finch, Cochabamba mountain finch, Saint Lucia black finch and Wilkins’s finch. And the critically endangered species list includes mangrove finch, medium tree finch, Nihoa finch, and Gough finch. Both the medium tree finch and the mangrove finch are among the 15 or so species of Darwin’s finches found only in the Galapagos Islands.

We chose one of the Darwin’s finches as our emblem for and this blog for their role in history, famous for inspiring Charles Darwin in his theory of evolution. At least some of Darwin’s famous finches might soon be driven to extinction.

The Wandering Finch is about ideas, projects, possibilities and solutions.

Parasitic flies brought to the Galapagos Islands most likely by humans in the 1960s are threatening to push some of the finch species of the islands to extinction. The parasitic larvae gorge on the blood of newborn birds in the nests. With a mortality rate of almost 100 percent in many of the finch species, the outlook is grim, yet there is hope on the horizon.

Several groups of researchers are working on a variety of possible solutions to help save these beautiful songbirds, including the concept of biological control, a method, sometimes controversial, of controlling one kind of pest or parasite using another. This practice has been successful in agriculture, but has not been much tested in conservation.

In the case of Darwin’s finches, they are studying the possible use of a parasitoid wasp to control the flies that are currently ravaging the young birds. In a different approach, Dale Clayton, a University of Utah parasitologist, in an article in The Christian Science Monitor described “self-fumigation.” He noted that birds look for soft materials to line their nests, which could include cotton balls sprayed with a small amount of a safe pesticide and placed near nesting sites.

Another idea, which has been used in this country, is to introduce sterile males to other problematic parasitic populations. The females that reproduce with these infertile males do not produce viable offspring, thereby reducing the population of the problem organisms.

The hope is that science can help nature save the Galapagos’ finches, which may produce new methods that can be applied to other threatened species.