A recent study by Robert Meese of the University of California states that the tricolored blackbird (Agelaius tricolor) species of the Central Valley of California has witnesses a major decline in its population and soon will be on the verge of extinction, if not checked. A survey conducted by the study along with the U. S. Fish and Wildlife Service, California Department of Fish and Wildlife and Audubon California, was released on Wednesday. It depicted that the tricolored blackbird now numbers about 145,000 in the state, 260,000 birds were counted in 2011. The number has fallen by 64% since 2008. These numbers are a huge blow when we consider that almost a decade ago the population of these birds was around a million. Even worst would be when we consider the fact that way back in 1937, the tricolored blackbirds' population was 3 million. The reasons for this huge decline can be explained by the drying up of the wetlands that were historically used as nests by these birds. These wetlands dried up because of drought and also because of the establishment of large farms that use pesticides. This pesticide use has declined the type of insects that this bird feeds on, be it caterpillars, beetles or grasshoppers. This reduction in food has caused the birds to reproduce just once instead of the usual two times that it earlier did.
Now, this bird population moved into fields where a wheat-rye hybrid used as dairy cattle feed is grown but the problem that arises here is that harvesting is done way before the young birds leave the nest.
To do the needful in this situation is very important so as to prevent the extinction of the tricolored blackbird like the two colonial bird species, the passenger pigeon and the Carolina parakeet. For this, Meese is working with large land owners to encourage them at providing habitat for these birds. Also, talks are on to create a nesting reserve at the Central California campus
Read more: http://newstonight.co.za/content/blackbird-population-declines-alarming…
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