Prairievogels

Sidamo lark will likely become the first known bird species to vanish from mainland Africa

The Sidamo Lark (Heteromirafra sidamoensis) is endemic to Ethiopia. Always a rare sight, the elusive bird may soon vanish from the prairie grasses of Ethiopia forever. Listed as Vulnerable since 2000 on the IUCN Red List, it was uplisted to Endangered in 2007, and then further to Critically Endangered in 2009. Its habitat already restricted to less than 100 square kilometers, the lark is rapidly losing territory as local residents, the Borana ethnic group, convert grassland into heavily grazed pasture. Unless the Borana are allowed to resume their nomadic ways, within the next few years the Sidamo lark will likely become the first known bird species to vanish from mainland Africa, researchers say.

A desperate bid to save the iconic sage-grouse from extinction in North America

The Sage Grouse (Centrocercus urophasianus) is the largest grouse in North America, where it is known as the Greater Sage-Grouse. Its range is sagebrush country in the western United States and southern Alberta and Saskatchewan, Canada. The greater sage-grouse is known for its elaborate courtship dance on the Prairies, but its enthusiastic display of virility might not be enough to save the endangered species from being wiped out in Alberta as soon as next year. A group of scientists hope to come up with ways to prevent the eventual extinction of the sage-grouse. Cliff Wallis from the Alberta Wilderness Association says the numbers have dropped to 30 in Alberta from the thousands 25 years ago. Wallis says the Alberta and federal governments are aware of the plight of the sage-grouse, but so far have failed to act. Cam Aldridge from Colorado State University says a similar decline of the species is occurring in the United States as well.

Pesticides are a critical factor in the decline of Loggerhead Shrikes in Canada’s Prairies

In Canada, the Prairie population of Loggerhead Shrikes Lanius ludovicianus excubitorides occurs in central and southern Alberta and Saskatchewan, and in southern Manitoba. They feed on grasshoppers, beetles, mice, small birds, snakes, lizards and frogs. Scientists observing a nest with eight nestlings watched as the parent birds appeared with a grasshopper every four minutes over the space of an hour! The last 100 years have witnessed the gradual decline of this subspecies. Pesticides are a critical factor in this decline.

Les insecticides granulaires induiraient des changements importants chez les populations de certaines espèces d'oiseaux dans les terres agricoles des prairies

Nous avons cherché à savoir si les insecticides, lorsque utilisés sous forme granulaire et de façon intensive pour contrôler l'altise (Phyllotreta sp.) dans le colza (Brassica napus et B. napa), jouent un rôle dans le déclin des populations d'oiseaux des prairies canadiennes.

Patterns of bird species abundance in relation to granular insecticide use in the Canadian prairies

We examined the possibility that granular insecticides, used intensively in the Canadian prairies to control flea beetles (Phyllotreta sp.) in canola (Brassica napus and B. napa), could contribute to bird population declines.

A retrospective analysis (1971–96) was done to investigate relationships between counts of 29 bird species made on Breeding Bird Survey (BBS) routes with a spatially explicit granular use index (derived from surveys made in 1980–85) and an index of land use change (derived from Principal Components Analysis of agricultural statistics) for 30 Census Agricultural Regions (CARs). Controlling for spatial location and the land use change index, abundance of American robin (Turdus migratorius), horned lark (Eremophila alpestris), house sparrow (Passer domesticus), mourning dove (Zenaida macroura), and western meadowlark (Sturnella neglecta) was negatively correlated with insecticide use; only two species showed evidence of a positive correlation. At a shorter time scale, for which we had direct estimates of pesticide use (1980–85), we also found evidence that the black-billed magpie (Pica pica), European starling (Sturnus vulgaris), and killdeer (Charadrius vociferus) were less abundant in areas where granular insecticide use was high. Population trends (% annual change between 1971–96) were negatively correlated with the granular index for horned lark, house sparrow, and western meadowlark. Although correlational only, our results suggest that granular insecticides may be an important factor influencing population changes in some bird species in prairie farmland.

A Disaster in the Making: A new book on the hazards of imidacloprid

A 72-page 2010 publication raises new and troubling questions about a widely used insecticide's potential for harm to bees, beneficial insects, and bird populations. Using imidacloprid as an example, Dutch toxicologist Dr. Henk Tennekes reports on the hazards of imidacloprid to insects and birds. Imidacloprid is a neonicotinoid chemical, and has systemic action in plants. Other European researchers have linked this insecticide to significant risks for honey bee populations, including possible links to Colony Collapse Disorder.

Dr. Tennekes' findings indicate that imidacloprid (and possibly other neonicotinoid-type insecticides) can bind irreversibly to critical receptors in an insect's nervous system. If these receptors are permanently blocked, the insecticide would not follow a typical dose-response curve. He provides evidence that long term low level to imidacloprid exposure can lead to neurological problems and eventual death of insects.

Studies have shown imidacloprid to be highly persistent in the environment (RCC Compendium of Pesticide Information). In his book, Tennekes presents data showing that imidacloprid has contaminated most of the waterways in the Netherlands.

Systemic activity in plants combined with long-term persistence in the environment and toxicity at low concentrations can be a dangerous combination. Many vulnerable species over large areas could be exposed to this insecticide on land, in surface water following runoff from treated areas and in groundwater due to its potential for leaching through certain soil types.

Several previous studies have shown that imidacloprid is highly toxic to various forms of wildlife, including honey bees, certain beneficial insects, upland game birds, and crustaceans

Tennekes further suggests that imidacloprid has led to a general decline in the insect populations in the Netherlands, and this lack of food in turn has been responsible for declines in bird populations.