Bird species dwindle in city, finds survey

Laxmi Prasanna| TNN | Updated: Dec 11, 2017, 23:37 IST

As many as 147 species of birds were spotted during the survey

Thiruvananthapuram: The recent survey conducted at seven sites in the city found that the number of bird species in the city has come down.

As many as 147 species of birds including rare and migratory birds were spotted during the survey carried out as part of Annual Bird Race 2017, organized by WWF-India with the support of Kerala forests and wildlife department.

"Over the years there is a decline in the number of bird species," said WWF-India state director Renjan Mathew Varghese. Construction activities, dredging and pollution in wetlands are the reasons for this, according to experts.

"The wetland bird 'Indian coot' used to be seen in groups at Akkulam earlier. But during the last three years due to the construction activity, dredging and pollution, such wading birds have started disappearing," said WWF-India education officer A K Sivakumar.

Read on  

City birds are smarter than country birds

Life in the city changes cognition, behavior and physiology of birds to their advantage

Date: March 21, 2016

Source: McGill University

Birds living in urban environments are smarter than birds from rural environments.

But, why do city birds have the edge over their country friends? They adapted to their urban environments enabling them to exploit new resources more favorably then their rural counterparts, say a team of all-McGill University researchers.

In a first-ever study to find clear cognitive differences in birds from urbanized compared to rural areas, the researchers report key differences in problem-solving abilities such as opening drawers to access food, and temperament (bolder) among city birds versus country.

The team tested the two groups of birds using not only associative learning tasks, but innovative problem-solving tasks. Innovativeness is considered to be useful in the "real life" of animals in the wild, more so than associative learning.

Video: https://youtu.be/KaE8z95KboE

"We found that not only were birds from urbanized areas better at innovative problem-solving tasks than bullfinches from rural environments, but that surprisingly urban birds also had a better immunity than rural birds," says Jean-Nicolas Audet, a Ph.D student in the Department of Biology and first author of the study published in the journal Behavioral Ecology.

Continued ...

Where The Birds Are Is Not Where You'd Think

This is a trick question. Where would you expect to find the greatest variety of birds?

Downtown, in a city?

Or far, far from downtown — in the fields, forests, mountains, where people are scarce?

Or in the suburbs? In backyards, lawns, parking lots and playing fields?

Not the city, right?

"Everything I have learned as a conservation biologist tells me cities are bad for biodiversity," writes John Marzluff, of the University of Washington.

We all know this. Anyone who goes to downtown Chicago, Toronto, Seattle, L.A., Boston or New York will see the same five birds over and over: sparrows, starlings, mallards (ducks), geese, and, of course, street pigeons. Same goes for downtowns in Europe, Asia and South America. These five bird types are always there, always the same, never surprising. Rather than yawn, scientists have a category for this: "biotically homogenous." We've made cities. They've moved in.

A Seattle Experiment

But now comes a surprise. Actually, several surprises. When John Marzluff and his students went to downtown Seattle to count bird species, within the first 10 to 15 minutes they spotted pigeons, finches, sparrows, crows and an occasional hummingbird. Their count was 10 to 15 different kinds of birds — not many, but they expected that.

When they went the other way (to the far edge of the metropolitan area near the Cascade Mountains, where there is mostly forest, protected parks, reservoirs, and humans are sparse), in the first 10 to 15 minutes, they found a very different set of birds (woodpeckers, wrens, warblers, chickadees ...). In all, 20 different species — more, but not many more than downtown.

Then they went to the in-between zone, the Seattle suburbs, where they expected an in-between count, something like 12 different kinds of birds. But that's not what happened.

Read on

City birds 'cope better in cold' than those in woodland

Urban breeding birds fared better than their woodland counterparts during 2012's cold, wet weather for the first time in 10 years, a study has found.

Blue and great tits in a woodland area were compared with those in Cambridge.

Researchers found urban birds relied less on a single source of food, such as caterpillars, whose numbers are affected by cold weather.

Woodland birds also bred less during the cold spell in 2012, said the Anglia Ruskin University study.

It was carried out in conjunction with the Centre for Ecology and Hydrology (CEH).

The British Trust for Ornithology (BTO) referred to 2012 as "one of the worst breeding seasons on record" following poor results in its annual surveys of nests and fledglings.

'Urban advantage'

The latest study concluded birds living in native British woodland were "more susceptible to the effects of extreme weather conditions than those in urban environments".

Continued

City birds adapt to their new predators

When a bird is faced with a predator, its only objective is to escape. However, city birds do not react in the same way as their countryside counterparts, despite being from the same species. Urbanisation plays an influential role in their survival strategies. 

To study this phenomenon, Juan Diego Ibáñez-Álamo, researcher at the University of Granada (UGR) and Anders Pape Møller from Paris-Sud University (France) analysed the escape techniques of 1,132 birds belonging to 15 species in different rural and urban areas. 

Published in the Animal Behaviour journal, the results show that city birds have changed their behaviour to adapt to new threats like cats (their main predator in the city) instead of their more traditional enemies in the countryside, such as the sparrow hawk. "When they are captured, city birds are less aggressive, they produce alarm calls more frequently, they remain more paralysed when attacked by their predator and they loose more feathers than their countryside counterparts," as explained to SINC by Juan Diego Ibáñez-Álamo. The surprising thing is that urbanisation is directly linked with these differences, which become more acute the earlier the former has taken place. This suggests that escape strategies evolve alongside the expansion of cities; a concept that is on the increase worldwide.

Read more at: http://phys.org/news/2012-11-city-birds-predators.html#jCp