Archive | September, 2013

Is Greed Ever Good for Conservation?

The short and unexpected answer is a resounding ‘yes.’ A study reported in Science by Joppa and colleagues determined that not only were two major goals for global plant conservation compatible, but a newly-designed priority-setting scheme for plants would in turn protect regions on the planet where large numbers of endemic birds, amphibians, and mammals also lived. Greed was an essential component to reconciling these several conservation goals.

A fundamental tenet of most conservation planning is to identify regions that contain many species. The Convention on Biological Diversity (CBD) aspires to formally protect at least 17% of the terrestrial world. Through the Global Strategy for Plant Conservation, the CBD also seeks to protect at least 60% of the earth’s plant species. The study by Joppa and his colleagues asked: are these targets of protecting area and species mutually compatible?

To solve this question, biologists at Duke and NC State universities teamed with computer specialists at Microsoft Research in Cambridge, England. Their solution relied upon a ‘greedy algorithm’ that accumulated species found only within a progressively larger set of regions. The greed refers to first picking the regions with the highest species densities (number per unit area), followed by areas that add progressively fewer new species to the aggregated total. In practice this meant that the first 43 regions were all islands, followed by tropical Costa Rica and Panama. A practical advantage of the greedy algorithm as noted by the authors was that this technique created a continuous, smooth curve of increasing areas and species.

This greedy algorithm revealed that 67% of plant species lived entirely inside regions that comprised only 17% of the planet’s terrestrial surface area. Whether the greedy algorithm was optimized for number of endemic species or for all species, it still gave similar results.

Interestingly, the greedy algorithm performed better than another widely-heralded priority-setting scheme – biodiversity hotspots. Indeed, the formal optimization used by Joppa and colleagues protected 59% of endemic species whereas hotspots could only corral 44% on that same amount of land area. The greedy approach also captured 74% of plant species, a number that the hotspot approach could not even estimate at all.

Best of all, plant regions highlighted with the greedy algorithm were good for the planet’s terrestrial vertebrates. Within the same 17% of the earth where two-thirds of all plants live, 89% of bird species, 80% of amphibian species, and 74% of mammal species also occur.

When it comes to setting conservation priorities, perhaps fictional Gordon Gecko was right: “Greed works.”

J. Christopher Haney, Ph.D.

Chief scientist

Defenders of Wildlife

Posted in ESA, Imperiled Wildlife0 Comments

Sage-Grouse: Ambassador for the Sagebrush Sea

When they’re not engaged in their flamboyant spring mating displays, greater sage-grouse spend the rest of year making a living on vast sagebrush grasslands in the West called the “Sagebrush Sea.” In fact, sage-grouse cannot survive without sagebrush, and they need lots of it. This makes sage-grouse an ideal “umbrella” species for sagebrush habitats. 

Umbrella species typically require large expanses of healthy habitat to survive. Because of that requirement, protecting these species also benefits other fish, wildlife and plants within these large areas. Animals of any size can be an umbrella species. Large carnivores, like grizzly bears, are umbrella species for the forests where they roam, and little insects, like the bay checkerspot butterfly, serve the same role for rare native grasslands where they occur.

Though their numbers are diminishing, sage-grouse still live on about 100 million acres in the West. Individual groups of grouse are known to migrate up to 100 miles every year as they move between seasonal habitats. These expansive areas include sagebrush habitat, but also lakes, rivers, streams, springs and wetlands, hot springs, aspen groves, alkali flats, salt flats, sand dunes and rocky bluffs.

Managed properly, this diverse mosaic of habitats supports hundreds of species of fish and wildlife, including the powerful northern harrier, the tiny pygmy rabbit, the fleet-footed pronghorn and the gorgeous Lahontan cutthroat trout. The sagebrush ecosystem is a migratory corridor for birds and important winter habitat for mule deer and elk. At least 15 species of raptors use sagebrush grasslands, and a full complement of carnivores inhabit the landscape, from weasels to mountain lions.

The pygmy rabbit is the smallest rabbit in the world. Adults measure 8-11 inches and weigh a half-pound to a pound. The pygmy rabbit is also one of only two rabbits that digs its own burrow. It is typically found foraging under stands of big sagebrush species on deep soils, an increasingly rare habitat type in the Sagebrush Sea.

Unfortunately, as sage-grouse have declined in the West, so have a multitude of other species. More than 350 plant, fish and wildlife species in the Sagebrush Sea are of conservation concern. Of these, approximately 60 species are listed or are candidates for listing under the Endangered Species Act.

Making matters worse, threats posed by improper land use, weed incursion, wildfire and climate change are increasing on the landscape. Continued habitat loss and degradation is threatening a suite of sagebrush birds, including the sage sparrow, Brewer’s sparrow and sage thrasher. Excessive pumping and water diversions are drying up streams and springs, imperiling native fish. Livestock grazing and fire have severely reduced habitat for the pygmy rabbit, and oil and gas drilling has eliminated winter range for mule deer.

Sage-grouse to the rescue!

Federal and state agencies are currently engaged in an unprecedented planning process to conserve sage-grouse across the West. The new plans will affect more than 60 million acres of public lands. If these agencies adhere to the science and abide by their own planning directives, the conservation measures they develop and implement for sage-grouse will have enormous benefits for other species. New land use restrictions, wildlife reserves and restoration programs would ensure that sage-grouse, and a multitude of other fish and wildlife species, survive and flourish on the landscape. Defenders of Wildlife is heavily involved in the planning process and invite you to join us in this important endeavor!

Umbrella species serve as ambassadors for the ecosystems where they live and, while many ecosystems have an umbrella species, few are as charismatic as sage-grouse. The Sagebrush Sea and all of the fish and wildlife that live there are fortunate to be represented by this charming bird.

Posted in Imperiled Wildlife, Public Lands0 Comments

dotWild is the blog of scientists and policy experts at Defenders of Wildlife, a national, nonprofit membership organization dedicated to the protection of all native animals and plants in their natural communities.