Thursday, September 22, 2011

Assabet River National Wildlife Refuge

Hunting is allowed in our neighboring wildlife refuge. Details first – the Massachusetts deer hunting season runs from mid-October to the end of December, is limited to bows, shotguns and muzzle-loading rifles, and never on Sundays. These are all short-range weapons compared to hunting rifles, hence lowering the risk of accidental shootings. The application deadline was back in July. The Assabet River National Wildlife Refuge also has hunting seasons for turkeys, grouse, woodcock, rabbits and squirrels. Deer hunters must wear orange. During hunting season, so should you.

Origins of the Refuge date back to the 1942 seizure of land spanning Maynard, Sudbury, Hudson and Stow by federal eminent domain. Landowners were given about ten days to pack up and leave, and by their own accounts received around ten cents on the dollar of what the land was actually worth.

Blueprint of munitions bunker [click to enlarge]
One of the most interesting features of the Refuge is the World War II era ammunition bunkers. The site was chosen to be convenient to railroad shipping to the Boston Navy Yard, which was active over the years1801-1974 and currently home to the USS Constitution, yet far enough inland so that a German battleship could not shell the area. Each of the 50 bunkers, officially referred to as “igloos,” has inside dimensions of 81x26x12 feet, with a curved roof. Sides and roofs were mounded with dirt for extra protection and disguise. Today, from all but the door end, these bunkers resemble small hills, complete with a forest of trees growing on top. Bunker #303 is sometimes open for tours. 

After WWII this site, referred to as the Fort Devens-Sudbury Training Annex, served as a troop training ground, ordinance testing and laboratory disposal area for Natick Labs, i.e., the U.S. Army Soldier Systems Center. A 1980s assessment led to this being categorized as an EPA “Superfund” clean-up site in 1990, as the site was contaminated with arsenic, pesticides and other chemicals. Extensive Army clean-up efforts continued for years, ending with the site being turned over to the U.S. Fish & Wildlife Service in 2000, to turn into a wildlife refuge.        

Tour of Bunker #303
The Refuge covers 3.5 square miles. The prime purpose is to manage land for migratory bird conservation. A website ( maintained by Friends of the Assabet River National Wildlife Refuge has maps, photos, activities, and a link to the government’s Refuge website. There is a wonderfully informative, child-friendly, Visitor Center at 680 Hudson Road, Sudbury. For people who just want to park and roam, the north parking lot is accessed from White Pond Road, reachable from Route 117 in Stow. Within the Refuge there are 15 miles of old roads and new walking trails, with the old roads, which are in poor repair, open to bicycles. No dogs allowed anywhere in the Refuge, no other pets, no horses, no fires, no overnight camping, no ATVs, no dirt bikes, no snowmobiles. Use of the Refuge is currently free, but that is likely to change. 

Back to deer hunting – this is an example of a need to manage a native species acting like an invasive species. Unrestricted hunting through the 1800s resulted in the New England extinction of wolves and mountain lions, and near-extinction of whitetail deer. But what with restrictions on hunting and return of farmland to wilderness, the state’s deer population is roughly 100,000 or 10 per square mile, and much higher in favorable terrain. Without population management of some sort, deer destroy ecological balance. ARNWR allows deer hunting so it will be a refuge for all wildlife, not just deer.
Trees growing on top of bunker, next to roof vent

One gray wolf made his way from Canada to western Massachusetts in 2007. Unfortunately he took up sheep killing rather than deer hunting, and was shot. A mountain lion walked from South Dakota to Connecticut, where he was then hit by a car in 2011. If more apex predators emigrate from the west then the Refuge will become a more interesting place to walk, as these animals hunt year round, including Sundays.     

Thursday, September 8, 2011

Death by Exercise, Marathon, Triathlon

Sudden cardiac death – as in the college-age basketball player or the hyper-fit triathlon participant – tends to make the news. As it should. Newsworthy death while exercising provides every non-exerciser with rationale for not exercising. “See” they say, “this person was an avid runner [cyclist, swimmer] and dropped dead at 40.” The contrarian point being that the endurance sports that are supposed to protect against heart disease sometimes appear to do just the opposite.

There is an iota of truth to this observation. Estimates are that just under one person per 100,000 participating in a half-marathon or marathon, or 1.5/100,000 participating in a triathlon race will die during or immediately after the event. The great majority of triathlon deaths occur in the swim phase. Figure a collective three million participants in these types of races each year and that comes to maybe 30 deaths per year. There are fuzzier estimates of perhaps one sudden death per every million exercise event for other forms of exercise. So the true answer is yes, exercise can kill the physically fit, but no, not a risk factor worth avoiding exercise entirely.

There is more truth in the observation that exertion by the physically unfit can result in fatal cardiovascular events. The classic case is the middle-aged office worker who drops dead shoveling snow while attempting to clear the driveway and get to work. Contributing factors include the fact that blood pressure peaks in the morning a few hours after waking up, and the fact that exertion in cold weather constricts arteries, further adding to heart stress (triathlon deaths in cold water probably for the same reason). Snow removal related heart attacks frequently occur in women and men with no known pre-existing heart disease.

Exercise can also result in accidental death. In the U.S., walking, running, bicycling, swimming, boating and winter sports add up to about 10,000 deaths per year. Subtract half who are either children or are adults under the influence of alcohol (as in walking or riding a bike home from a bar, at night), and it’s still a big number. But the total pales compared to the 2,500,000 total deaths per year, of which many are premature cardiovascular deaths brought on by a lifetime of inactivity.

The good news is that benefits from even modest amounts of exercise are becoming clearer. In a 2011 article in The Lancet, C.P. Wen and co-authors reported that for a multi-year tracking study of 416,175 Taiwanese adults, as little as 90 minutes per week of moderate-intensity exercise reduced the risk of death by fourteen percent. Each additional 90 minutes per week added four percent further reduction. Other studies have also reported the greatest improvement for modest exercise compared to no exercise at all, and diminishing returns for progressively more exercise.

The theory that over-doing exercise may cause more harm than good has neither been confirmed nor disproven. A science journal article by Masaru Teramoto reviewed fourteen studies of longevity of elite athletes. Athletes from endurance sports had 3-6 year longer life spans than the general population, but the results were mixed for athletes in power sports. The latter may be disadvantaged by larger body size typical of their sport or from a discontinuation of exercise as they age. The authors caution that elite athletes may by genetically different from the population as a whole, with both their abilities and lifespan being consequences of their genes rather than one causing the other.

There is a non-fatal problem with exercise – it is potentially addictive. As one well-known fitness expert author put it, “…people reduce their lives to fitness routines, training as many as 40 hours a week. That the effort may wreck marriages and compromise immune systems isn’t even relevant. To these people – demographically a diverse lot – exercise is addictive. The more the body gets, the more it wants. In return, the drug of exercise infuses the swimmer, cyclist and runner with two powerful illusions: that he/she is escaping the horrible, and progressing toward the divine.”

Beyond the story: Exercise-related articles on this blog include "Avoiding Overhydration" (Feb 2010), "Hypothermia" (Nov 2010) and "Recovery from Donating Blood" (March 2011). For a detailed, referenced take on death from exercise, go to the entry "Sudden Death and Exercise", in the Encyclopedia of Sports Medicine and Science: