New study shows many bears still rely on dwindling whitebark pine seeds
The long-term survival of grizzles in the Greater Yellowstone ecosystem may depend on whether they’re willing to switch from eating whitebark pine seeds to other types food.
Some of the bears have already started responding to reductions in whitebark trees by consuming more plants and berries, while others are still focused on finding stashes of the nutritious pine nuts, scientists said in a new study based on analyzing the chemical composition of what the grizzlies eat. Continue reading “Can grizzlies survive global warming?”→
Saving monarch butterflies means planting a lot of their favorite food, say U.S. Geological Survey scientists, who outlined conservation measures in a new study.
After over-wintering in Mexico, monarchs rely on milkweed plants for food and breeding habitat. But milkweed has been wiped out across millions of acres. The new study measures the need in terms of stems of milkweed.
In the northern U.S. at least 860 million stems were lost during the last decade. After studying the density of Eastern migratory monarch butterflies overwintering in Mexico from 1979-2002 and the amount of milkweed plants available to them in North America. The study found that 3.62 billion milkweed stems are needed to reestablish this monarch population, but only 1.34 billion stems remain in the U.S.
“Monarchs in eastern North America are a beloved insect, but they’re in jeopardy, partly due to the loss of milkweeds in cropland,” said Wayne Thogmartin, a USGS scientist and the lead author of the report. “Our study is important because it helps specify the conservation needs of this charismatic species.” Continue reading “To save monarchs, plant milkweed — lots of it!”→
Population expected to double in the next 50 years
Biologists say current conservation efforts for Florida’s manatees should suffice to help the marine mammals survive for at least the next 100 years. If resource managers continue to protect manatees and their habitat, there’s less than a half-percent chance the population would drop below 500 individuals, the level that would threaten long-term survival.
The new study was done by the US Geological Survey and the Florida Fish and Wildlife Research Institute. It found that Florida’s manatee population is likely to gradually double over the next 50 years and then level off. Over time, environmental and habitat changes will probably cause manatees to become less abundant in South Florida and more numerous in North Florida, but the population as a whole will remain high. Continue reading “Study says Florida manatees safe for now”→
A fungal pathogen that has wiped out bat populations across the eastern third of the U.S. has now been found in Texas, according to state wildlife officials, who documented the fungus for the first time on two new bat species: the cave myotis and a western subspecies of Townsend’s big-eared bat.
White-nose fungus first emerged in 2006 in New York and his since spread into 30 states and killed at least 5.5 million bats. Wildlife conservation advocates said the recent announcement from is a biological disaster, considering the potential risks to huge, world-famous bat colonies that thrive in unique cave ecosystems in the state. Continue reading “Bat-killing fungus spreads to Texas”→
Toxic lead is back on the menu for many wildlife species, as newly appointed Interior Secretary Ryan Zinke revoked a U.S. Fish and Wildlife Service order that had banned lead hunting ammunition on federal wildlife reserves after a years-long campaign by wildlife advocates.
The USFWS order was finalized the day before Donald Trump was inaugurated as president. In his reversal, Zinke made no reference to the extensive body of science showing that lead ammunition is harmful to wildlife.
The threat of roads to carnivore species around the world has been seriously underestimated, according to a new study that looked at the issue on a global scale.
After looking at 232 carnivore species around the world (out of a total of about. 270 existing species) and assessing how severely these are affected by roads cut through their habitat, the researchers concluded that some rare species are even at risk in areas with low road densities. The study, published in the journal Global Ecology and Biogeography, calculated natural mortality rates, reproduction and carnivore movement patterns, determining the maximum density of roads that a species can cope with. Continue reading “Study says road threat to carnivores is underestimated globally”→
Small hibernating bat colonies need protection to prevent extinction
Between collisions with wind turbines and deadly white-nose syndrome, endangered Indiana bats may not have much of a chance of recovering, according to a recently published U.S. Geological Survey study.