Birds in Trouble

A visit to the California Academy of Sciences, located in San Francisco’s Golden Gate Park, speaks volumes about the disaster that has befallen birds with the spread of humanity. A maze of narrow corridors in the scientific collections leads an explorer to the Ornithological Collection. There you will find a cabinet with a sign: “Extinct Birds.”


A well-known scientist, Warwick Kerr, thought that by hybridizing African and Brazilian bees he might be able to create a strain that was both calm and yielded a rich lode of honey. But before Kerr could do the experiment, a Brazilian beekeeper visiting Kerr’s lab deliberately allowed some of the African bees to escape. That beekeeper’s motives are unknown, but besides possibly hastening the exit of Spix’s macaws, he has been responsible for the deaths of numerous human beings.

In a poignant twist, the last known wild male Spix’s macaw was discovered in 1990 paired with a female, but the female was not of his own species. The male Spix was trying to reproduce with was a female blue- winged macaw. The mismatched couple did mate, and she even laid eggs, but, as one might expect, the eggs were infertile.

More than seventy Spix’s macaws now live in captive breeding programs run by conservationists. To counter the risk of losing genetic variability due to inbreeding, individuals have been exchanged between various institutions in an effort to maintain their genetic diversity.

Smart Birds Make the Worst Parents

After patching up the hawk mount I continued my experiment, but I also wanted to know how both parents responded to a predator after having invested even more in their offspring. Since both parents feed their chicks, I conducted similar trials once the chicks had hatched and the parents were feeding them as nestlings. I found that both when parents were incubating, and when they were feeding their nestlings, they were hesitant to enter their nests in the presence of these ‘hawks’. However, the parents responded differently depending on how far up the mountain they lived. If they were from high elevation, the parents were much more likely to be scared away by the ‘hawk’ predator.



To find out whether chickadees that live high up behave differently in response to predators, I carried out an experiment. To do this, I placed a tripod at the entrance to a nestbox and scrambled away to become one with a distant pine tree, while keeping my binoculars trained on the recently departed female and the nest. When the female returned, what did she do? The mother stopped short of the nest area, rather than ‘bird’-lining it straight for the entrance. She was agitatedly hopping from branch to branch scolding the hawk for being near her nest. She flew off, only to return later. Eventually, she entered the box to make her eggs hot.


How might these unexpected results be explained? One possibility comes from a study on a closely-related English bird called the Great Tit (leave it to old English men). Ella Cole and her colleagues found that parents who were better at solving a novel problem were also more likely to abandon their offspring when disturbed. High elevation chickadees, like their problem-solving cousins, have superior cognition compared to their less smart low elevation counterparts. Mountain Chickadees use food-storing as a way to survive winter. Since high elevation chickadees contend with harsher environments, they have superior spatial memory than low elevation chickadees, allowing them to recover enough stores to survive more severe winters. So, could it be that there is some kind of trade-off between being smart and being willing to take a risk? The reason behind these results remains intangible, but maybe smart individuals just make poor parents.