Wednesday, May 10, 2017

Wolves Repopulate Massachusetts - NOT!

Before Europeans arrived in North America, what is now the 48 contiguous states, i.e., all but Alaska and Hawaii, was home to an estimated 250,000 wolves. And 10 to 20 million deer. Nowadays the estimates are 5,500 wolves, and 25 to 30 million deer. There has been lobbying to restore wolves to the east, much as was done for bald eagles, but no action expected in the near, middle or distant future. Because it is one thing to restore the national symbol, and another to have the big, bad wolf wandering about the Berkshires.  

The anti-wolf movement started ten years after the Mayflower landed. In 1630, the Massachusetts Bay Colony approved a bounty for each wolf killed. Other colonies followed suit, at times switching back and forth between bounties paid to anyone and professional hunter/trappers. The first cause for this animosity was to stop depredation of domestic animals - cattle, sheep and pigs. Wolves had been eradicated in England and Scotland long before colonization to the Americas, so while the settlers had folklore of the depredations of wolves, actually losing livestock was a rude jolt.

By 1840 there were no more wolves in Massachusetts. Henry David Thoreau had lamented that of New England's wild life, nothing larger than foxes remained. Wolf extirpation followed in neighboring states, so by 1900 there were no more wolves in New England.

The practice of killing wolves to make land safer for pastured sheep and cows shifted west as Americans moved west. In time, a second cause evolved. The early decades of colonization treated wildlife as an inexhaustible resource. Deer were hunted for family consumption, but also for the market for meat that grew as cities grew. In time, game became scarce, hunting for market was banned and the concept of licensed sport hunting matured. Wolves were hunted, trapped and poisoned so there would be more deer and elk to be shot for sport. Anti-predator attitudes extended to mountain lions and coyotes.  

What was learned, slowly, was that without apex predators, herbivores will multiply to beyond what the greenscape can support. Starting in 1994, a great experiment was conducted in and around Yellowstone National Park. Thirty wolves were trapped in Canada and released in the Park. Within ten years the population peaked at approximately 300. It has since declined to half that due to pack-to-pack competition for territory and out-migration. The elk population declined from 20,000 to what may be a stable 5,000. Mule deer, moose and bison populations showed little change. Spending by hunters is way down, but is more than compensated by wolf-related tourism. 

There have been other interesting consequences. The coyote population has been halved, but the grizzly bear and cougar populations stayed stable. Bald eagles and ravens - scavengers at wolfkills - increased in number. With the end of over-grazing by elk much plant life recovered, bringing biodiversity.

The concept of "ecology of fear" came out of this experiment. When animals continuously fear predators, behavior changes. More time spent on surveillance and staying nearer to safe havens means less time eating. Less time eating slows growth and reproductive success. Locally, our examples of animals without fear include turkeys and geese.       

Looks like lunch! (Internet download, click on photo to enlarge.)
There are proposals to restore wolves to upstate New York and northern Maine, which in time would result in populating surrounding regions. A big question: Will wolves attack people?  Nineteenth century newspaper accounts describe wolf packs attacking and eating children, adults, even armed adults who managed to kill some of the wolves before dying. Wolf attacks on humans are very rare now, but the main cause is that wolves are rare. What is being reported are increasing numbers of attacks on dogs. Hunters that use off-leash dogs for licensed bear hunting are reporting dog kills in Idaho, Wisconsin and other states. Pet dogs have been taken in parks in Minnesota.

There is an argument for a net benefit from restoring wolves to the east. Currently, 150-200 people die each year from vehicle collisions with deer. Restoring wolves would reduce that number, perhaps at the cost of 1-2 deaths per year from wolf attacks. Logical? Yes. Emotionally reassuring? No. One solution would to be equip a wolf or two per wolfpack with a GPS device and have a wolf app on your smart phone.

Not in the newspaper column: In 2007 a wolf was shot in Shelburne, Massachusetts, after reports of an animal killing sheep and lambs. DNA testing confirmed the 85 pound male animal as a gray wolf. The nearest known wild wolf population was in Canada, some 350 miles away. Back in elk country, the estimates are that wolf packs will kill 22 elk or other large ungulates per wolf per year. Deer being much smaller, it could mean more than 50 deer per wolf per year! Meanwhile, there have been scores if not hundreds of documented coyote attacks on humans, sometimes by rabid animals and sometimes not. Two attacks have resulted in deaths - a three year old child (1981), and a 19 year old woman (2009). Rabies more commonly affects raccoons, skunks and foxes, but can cross to coyotes. A common sign of rabies is a loss of fear of natural predators (and humans), abnormal behavior, such as being active during daylight hours for a species typically nocturnal, and aggressive biting.      

Wednesday, May 3, 2017

Bald Eagles Repopulate Massachusetts

Bald eagles don't have to be fast, only strong. The majority of their diet is either fish or stuff already dead, competing in the latter situation with vultures, ravens and crows. Adults weigh 9-13 pounds (females are larger than males), and can easily lift a 3-5 pound fish out of the water. An eagle that ends up in the water - perhaps after grasping a too-large fish - can take off from the water's surface. Bald eagles also prey on young Canada geese, ducks and small mammals. And steal food from other predators, such as ospreys.

Bald eagle, Lake Boon 2011 (Martin French)
Bald eagles are in the genus Haliaeetus, common name sea eagles, of which the Steller's Sea Eagle* is the largest. Of the some 60 eagle species worldwide, our bald eagle does not make the top five for weight or wingspan. All eagle species are long-lived. For the bald eagle, lifespan in the wild often exceeds 20 years. In captivity, lifespan has been known to exceed 50 years.

During nesting season the mated pair are both involved in egg-sitting and bring food to the young - typically two - eaglets. The parents each need close to a pound of food per day, and the growing eaglets not much less, so an adequate food supply is essential to raising a family    

According to the Commonwealth of Massachusetts, there were 56 nesting pairs of eagles in the state in 2016, up from 51 the year before. The process of restoring eagles to this state began in 1982. Over a six year period, 41 eagle chicks were collected in Canada and released in the Quabbin Reservoir area. The chicks fledged, i.e., reached flying age, at 11 to 12 weeks. Most survived the next critical period of six weeks during which hunting, flying (and landing) skills were improving. In a normal situation the young chicks would have been fed every 4 to 5 hours by their parents, but in this relocation program the human caregivers wore a hand puppet that looked like an adult eagle's head. The effort to restore eagles to Massachusetts was part of the federally funded Northern States Bald Eagle Recovery Plan. 

Bald eagle with a fish (Internet photo). Click on photos to enlarge
The effort worked. Young eagles take four to five years to reach sexually mature adulthood, including a slow transition from juvenile all-brown tones to adult coloration, during which time they wander hundred of miles but tend to return to the general area where they were born to seek a mate and start raising families. By 1989 the relocated eagles were starting to nest in the Quabbin region. Since then, nesting sites have been spreading east and west. The nearest to us is in Framingham. Any local eagle sightings are of wanderers - either juveniles that have not yet paired up or adults during the non-nesting part of the year, which runs from mid-July to mid-January.

Juvenile bald eagle lacks the white feathered head and  tail,
and beak has not yet turned yellow. (Internet photo)
In Colonial times, an estimated 250,000 to 500,000 bald eagles populated what would become the continental United States, i.e., excluding Alaska and Hawaii. But by the 1970s, through a combination of hunting, loss of habitat and the unexpected effects of DDT spraying for mosquitoes, the number of nesting pairs had dropped to under 500. Through a combination of banning of DDT in 1972, the Endangered Species Act (1973) and the relocation programs, nesting pairs now exceed 10,000 and the species is no longer considered endangered. It is still protected by the Bald and Golden Eagle Protection Act.**

Lead poisoning continues to be an issue. The most significant hazard to wildlife is through direct ingestion of spent lead shot and bullets, lost fishing sinkers, or through consumption of prey containing lead shot or bullet fragments. While lead was federally banned for waterfowl hunting in 1991, its use in ammunition for other hunting remains widespread.

For many years, I half-remembered, or perhaps remembered half, of a short poem about birds of prey. While not specifically about bald eagles, it does capture a predator's sudden brutality. As remembered:

In the woods, I heard a scream.
Whether it was bird of prey
   or prey of bird,
I do not know, I only heard.

And then, while working on this column, I remembered the book I had read it in. So, as actually written:

BY NIGHT
After midnight I heard a scream.
I was awake, it was no dream.
But whether it was bird of prey
Or prey of bird I could not say.
I never heard that sound by day.
   - Robert Francis

*Steller's Sea Eagle: Georg Wilhelm Steller (1709-1946) was a naturalist on a Russian expedition to the Bering Sea in 1740. This eagle is 1.5 times the weight of the bald eagle. Adult females are known to top 20 pounds. Diet is mostly fish. In addition to the sea eagle, other species bearing his name are the Steller's Jay, Steller's Sea Lion, and Steller's Sea Cow. The last, a relative of manatees and dugongs, was hunted to extinction within decades after Steller's identification of the species.
Adult Golden Eagle (Internet download)

**The Golden Eagle is native to North America, but unlike the Bald Eagle, not limited to North America. Golden Eagles prey primarily on small mammals, and prefer open plains and mountains to densely wooded terrain. But they do wander east as far as Massachusetts, and can be mistaken for immature Bald Eagles. The original federal Act (1940) protected only Bald Eagles, but was extended to cover Golden Eagles in 1962.