Nature photography is about more than taking good pictures. Besides knowing how to operate a camera, the complete nature photographer should have an appreciation of the natural history of the subjects being photographed and a respect for their well-being.
There is perhaps nothing in nature more beautiful than a skein of Snow Geese beating their way across a clear blue sky, white wings illuminated by a bright sun. Capturing this scene is every nature photographer's dream. But for photogs new to Bosque and for veterans perhaps not yet aware, may I respectfully emphasize once more that there is a very serious light goose (Greater and Lesser Snow Geese, Ross's Geese) overpopulation problem in North America? Light geese are destroying not only the tundra habitat of their own breeding grounds in arctic and sub-arctic regions but also those of other species. The situation has been termed "an ecosystem in peril".
I published information about this problem, complete with many references, in a lengthy NSN thread in 2012:
viewtopic.php?f=1&t=222034
This thread was abruptly terminated by NSN in what seemed to be an attempt to suppress information.
Here are some recent updates on this dire situation:
http://www.npwrc.usgs.gov/resource/birds/snowprob/
Following are 2 models applicable to the overpopulation control problem.
Control Model 1:
Light geese begin breeding in their second year and may live as long as 20 years. The average clutch size is ~4. According to a simple 'actuarial' model I devised, in order to decrease the light goose population by 5% every year, for a family of 6 it would be necessary to increase the annual mortality rate to ~68.3%. The break-even mortality rate (no population gain/loss) is ~66.7%. The mortality rate for the current ~5-7% annual population gain is ~65.0%. (A continuing 5% annual gain will double the population again in ~14 years, in 10 years if 7%; cf. the 'Rule of 72' used in financial investing.) This model indicates that relatively small changes in the mortality rate could reverse the current population explosion. The problem is that the light goose population now numbers in the tens of millions and an increased harvesting of hundreds of thousands of birds per year would be required. Like a mouse trying to stop a stampede. A second problem is that this increased mortality rate must be applied to the whole population, not just a small fraction, and that this rate must be maintained for many years until the ecosystem is in balance again. After that the break-even rate should suffice.
This model is oversimplified in that it does not properly account for non-breeding birds - juveniles, unmated, gays(?), elders. But as each pair of breeding geese may produce 50-100 goslings, theirs is by far the most important contribution to the total population. Thus the mortality rate figures in my simple model should be reasonably good estimates.
Control Model 2:
Again, according to the Rule of 72, a 50% reduction of the total goose population in 10 years could be accomplished either by applying a tapering reduction of 7% annually, or by a reduction in equal slices of 5% of the starting population. But this model will not work, because only a minor fraction of the total population is affected. Meanwhile the major fraction will continue breeding, increasing the total population by 5-7% annually. The net result would essentially be a wash. To achieve the desired population decrease, it would actually be necessary to apply a ~14% annual reduction rate. For a 25-million bird base, this would require a harvest of ~3.5 million birds in the first year alone!
Some proposals aim to reduce the current Ross's Goose population of ~3,000,000 to 100,000, its population in the 1960s, but there has been strong opposition from the public in Canada. Note that the current population level is consistent with an annual increase of 7% over the last 50 years. Every 10 years the population has doubled: 100,000, 200,000, 400,000, 800,000, 1,600,000, 3,200,000 ........ The numbers are staggering!
Such models, and more complex ones, are used by North American wildlife service agencies and their professional biologists and refuge managers to assess the welfare of light geese and breeding habitat and what needs to be done to achieve a balance.
Imagine the consequences if the light goose population explosion is allowed to continue at its present rate. The arctic tundra habitat has already exceeded its support limits. Immediate action is required. Owing to the huge numbers of birds involved and the remoteness of their breeding grounds, reducing their populations in any substantial way is a daunting task. The only effective methods currently being applied are hunting and restriction of food supplies for migrating birds but these have proved inadequate. Culling and egg destruction are possible harsher alternatives. (For an excellent comprehensive discussion, see
http://www.nodakoutdoors.com/snow-goose-genetics.php.) Ultimately, a military-style assault may be required to eradicate the surplus of light geese, while still protecting other tundra-nesting species.
If these goals are not met, the light goose population will inevitably crash due to starvation, malnutrition and disease. Survivors may be too weak to migrate.
For a hunters' perspective, see:
http://www.huntupnorth.com/hello-world.html
The Bosque del Apache NWR is operated by USFWS, which is a partner in the North American Waterfowl Management Plan (NAWMP):
http://www.fws.gov/birdhabitat/NAWMP/index.shtm
http://www.nawmprevision.org/
The managers of the Bosque Refuge have a particularly difficult task in fulfilling this plan because many conflicting interests must be considered, both avian and human. These were discussed at length in my 2012 thread and earlier comments:
viewtopic.php?f=1&t=221867&p=2152676&hilit=207255#p2152676
viewtopic.php?f=1&t=221867&start=20)
The post by Sandy Corless in the present thread suggests that the Refuge is following the NAWMP.
Hopefully, visitors to Bosque this Fall will find this info eye-opening and relevant and that it leads to a greater understanding of waterfowl management. I hope you get some great pics. But please also appreciate what is happening and what needs to be done.
I will visit the SNOW GOOSE FESTIVAL OF THE PACIFIC FLYWAY at Chico, CA in January. Many of the Snow Geese wintering there originate from Wrangel Island off the northern coast of Siberia. I visited the nearby Sacramento NWR in November a few years ago and was astonished by the number of geese. I estimated 150,000. It seemed as if every square foot of space on the dikes was occupied by a goose.
The Festival has a juried art show where I will exhibit some of my fine art prints.
JM