Discover – September 2019

(Greg DeLong) #1

SEPTEMBER/OCTOBER 2019


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DISCOVER 59


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be a higher risk [for the birds], and that’s habitat loss and habitat


degradation.”


Lake Natron was recently under threat from a proposed


soda ash mine. Workers would extract sodium carbonate in


the lake so it could be sold as a chemical additive. (Sodium


carbonate is used to manufacture a wide range of products


from glass, to foods, to soaps.) But the project was relocated


after a years-long battle. The Kamfers Dam site saw similar


threats from a proposed housing development, and recent local


media reports say there’s a new proposal in the works to develop


adjacent to the site. Despite the flamingos’ adaptations, if a


development drained water levels or brought new pollution


that wiped out a breeding site, it would be bad news for the


dwindling birds.


Another challenge is that there’s much scientists still don’t


know about flamingos. “It’s a difficult species to work with in


the wild,” says Harebottle. “We’re going on a lot of assumption


work. Do birds that are born at the dam come back to breed at


their [birthplace]? That is unknown.”


That’s because their remote breeding locations make them


hard to study. The Kamfers Dam site is unique because it’s so


close to a major town — Kimberley — and the nesting birds are


visible from shore.


And it’s precisely this reason that made the January rescue


mission at Kamfers Dam possible in the first place. Never before


had a mass chick-abandonment been noticed with enough time


left to save the chicks.


EVERY BIRD MATTERS


When volunteers first arrived to Kamfers earlier this year, they


were met by an eerie scene. A flamingo’s nest looks like a mini


volcano made of mud and stones. And at a major breeding


ground like this, each nest is only a few feet from its closest


neighbor. The nests dotted the area by the thousands. But


instead of being surrounded by a noisy flock of parents, atop


every nest was either a single unhatched egg or a single newborn


chick, quietly struggling in discomfort.


The teams got to work. Volunteers loaded 30 chicks at a time


into small, flat cardboard boxes with air holes poked in the top.


Climate models project that some places will get wetter, while


others will be drier, so it’s a lose-lose outcome for these shallow


habitats. They “are very vulnerable to these extreme changes in


weather,” says Arengo.


And even such hardy birds can only take so much. “Now, with


climate change, these variations will become more extreme,” she


says. “And although the flamingos are adapted to having these


options, at some point, they’ll run out of options.”


That scenario has already started playing out. Shortly after the


rescue back in January, 5,000 more chicks were abandoned at


Kamfers Dam in February due to drought at a separate part of


the same site; luckily, these chicks were just old enough to make


it through on their own. On the flip side, when the water is too


high, the birds either can’t build their nests or, if the timing is


wrong, just-built nests are flooded, drowning eggs and chicks.


The latter happened in 2009 at the same location.


NEAR THREATENED


It’s not just water levels the birds have to worry about.


Populations of the microorganisms that flamingos eat can also


fluctuate dramatically in these shallow lakes, but researchers are


still figuring out why. One team that’s focusing on cyanobacte-


ria in particular suspects that outbreaks of cyanophages — or


viruses that attack the algae — could be a main culprit.


Regardless of what’s causing these fluctuations, they have a


big impact on flamingo populations. When algae populations


crash, the birds have to move on or starve. Alternatively, when


the algae experience abnormally large blooms, they can poison


the flock: Almost 44,000 dead were counted at Tanzania’s Lake


Manyara in 2004.


The nesting colonies are also susceptible to disease outbreaks.


Over 1,000 birds died of avian botulism at Kamfers in 2013.


The cause of other mass die-offs remains a mystery. After


30,000 birds died in a single week in 2008 at Lake Bogoria in


Kenya, researchers searching for cyanotoxins in the dead birds


couldn’t find any.


On top of all that, the more pressing concern is how humans


affect the birds, says Doug Harebottle, an ornithologist at


Sol Plaatje University, which is just a few miles from Kamfers


Dam. “I think there are other factors at play that could probably


The cause of other mass die-offs remains a mystery. After 30,000


birds died in a single week in 2008 at their breeding site at Lake


Bogoria in Kenya, researchers searching for cyanotoxins in the


dead birds couldn’t find any.

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