Mercury is a very common pollutant that affects the health of birds, as well as other wildlife. Despite being a common element in nature (water, soil and air), exposure or ingestion of any of its forms can damage your body.
However, some species are capable of developing their own techniques to remove these toxic compounds from the body. This is the case of two species of songbirds: the zebra finch (Taeniopygia guttata) and the European starling (Sturnus vulgaris) that manage to get rid of the mercury while changing their feathers. The study is published inEnvironmental Toxicology & Chemistry.
The experts came to this conclusion after observing that, when these songbirds molt, the mercury in the blood drops rapidly at the same time as the concentrations in other tissues are markedly reduced.
Greater removal of mercury than other birds
"It was not a surprise that shedding the coat accelerated the removal of mercury, but we did not expect the data to be so different from previously observed in other non-song bird species," says Margaret Whitney, a co-author of the paper and a researcher at the College. of William & Mary (USA)
This beneficial process, along with the migration of birds to uncontaminated locations, could help birds cope with exposure to toxic elements.
"Understanding the differences between species and how molting contributes to mercury removal can improve risk assessments," concludes Whitney.
European Starlings forage for food in meadows, fields, and any other open area with short vegetation. They search the ground by quickly pecking at the ground with their beaks closed and using the strong muscles of their jaws to open their beaks into the ground to search for insects and other invertebrates. They tend to forage with heals, cowboys, thrushes, sparrows, House Pigeons, Spring Blackbirds, and American Crows.
Observing flocks of starlings can help you understand how these gregarious birds communicate with their neighbors. European Starlings demonstrate that they are upset by flapping their wings, or looking defiantly at their adversaries while standing upright, holding down their feathers, and ruffling the feathers on their heads.
Submissive birds crouch and retreat with their feathers down. Starling confrontations can become more intense and end in deep and strong shoving and pecking. Birds standing on wires may even corner others by sliding on the wire and forcing others to move until they run out of space.
Males court females by singing near a nesting site they have claimed as their own, and at the same time flapping their wings in circles. After they have mated, the males follow the females everywhere, scaring off other males that approach them.
European Starlings are extremely aggressive and can dislodge other species of birds from their nests to use the sites and make their own nests. Among the species of birds that starlings can displace are Rainbow Ducks, Nun Ducks, Common Pechero Woodpeckers, Traveler Tufts, Bicolor Swallows, and Cinnamon Throat Blue Jays.
The zebra finch comes from Australia where it lives especially near water on large surfaces. A bottle-shaped nest is made among the dense grasses and bushes. This little singer was brought to Europe for the first time in 1790.
The adult finch measures 10.5 cm, the tail is 3.5 cm. The finch originally has a soft cream color on top of the head, neck and back. The males have red spots and a strong reddish beak and usually the cheeks as well. Today there are many different types of finches that are raised, for example: white, black, silver, tan etc.
The female lays 4 to 7 eggs. The young hatch from the egg after 11-13 days.
It is ideal to breed the finch in a group - just as it lives in the wild. But it can also be raised alone. It is a boisterous bird that chatters gracefully.
Food: Borona (ideally the ears), grains of grass plants, rapeseed grains, birdseed, fruit and vegetables, fresh dandelion and lettuce leaves, dry mix of eggs, sponge cakes. Mineral supplement in the form of cuttlefish.
The finch lives for approximately 5 years.
M. Whitney, D. Cristol. "Rapid depuration of mercury in songbirds accelerated by feather molt".Environmental Toxicology & Chemistry, July 20, 2017. DOI: 10.1002 / etc.3888
With information from: