Tuesday, February 14, 2012

Canada Geese invasion


Pender Island golf course on a January day
      I've written about this before, but it seems like there are more Canada geese than ever on our farm.  There is a golf course just down the road at the end of our valley, and we have big open fields, inviting ponds, and a very attractive place for Canada geese, it seems.  Sometimes there are so many of them it is a bit like an old Hitchcock movie.
    Prior to the 1960’s Canada geese sightings were rare treats but now they are commonly seen year round, and are more numerous each year. In the period from 1965 to 1995, the Canada geese in the Christmas bird count in the Fraser Valley increased 50 fold. Where no more than 200 Canada geese were seen in Victoria in the 1970’s, now over 5,000 are counted each winter. I can easily count over 200 Canada geese on our farm alone in the winter. The resident non-migratory geese made up 18 per cent of the North American total in 1970; now they account for 67 per cent. So what has happened?
      Since the early ‘70’s Canada geese numbers have been increasing significantly due to a perfect storm of events. A successful conservation program was launched across North America in the 1960’s by various wildlife agencies to restore numbers of geese reduced through years of hunting and habitat loss. The program was also intended to boost Canada geese numbers for recreational hunting purposes. In Canada there are 11 subspecies of Canada goose and eight of these live in B. C., but the two subspecies that were introduced through this program were resident, or non-migratory, geese not common to this area. The parallel increase in growth of urban and suburban communities with manicured lawns, golf courses and airports and lovely ponds made for the perfect Canada goose habitat. When we add restrictive hunting and firearm regulations and a lack of predators we have indeed created the perfect storm of events.
       It shouldn’t be a surprise that farmers view Canada geese as pests. Forage producers watch as hay and grain fields are demolished in a feeding frenzy by these foragers, which consume up to 4 lbs. of grass each day, depositing 2-3 lbs. of fecal material. A few years ago we spring-planted two fields with oats and millet, and watched as hundreds of Canada geese ate the crop while it was trying to grow. The geese kept the area stripped clean and the only crop we ended up with were thistles. After a lot of work dealing with thistles and re-working the fields with a fall-plant of rye and grass I hope our goose problem will not repeat itself. It takes daily visits to chase the geese off, though. Some farmers use dogs, balloons, decoys, barriers, fences, and propane cannons to keep them from eating crops.
      Not just grass and grains can be affected. Crops like leafy salad greens, cabbages, potatoes, carrots, corn and blueberries are also eaten by Canada geese. It is estimated that the annual damage to all farms in the Saanich Peninsula and Metchosin area is $300,000 per year.
      The ground next to the ponds is compressed and especially lacking in vegetation. This is only compounded by the fact that the federal government has been encouraging farmers over the past few years to dig more ponds to enhance our water storage.
      Now, some might suggest that golf course managers might think a bit about working with these lawn mowers with wings, since they produce fertilizer and keep the grounds manicured. But they are in fact viewed as an unappealing nuisance since the fertilizer tends to be slippery underfoot and muck up the golf balls. Recently our local golf course has placed two lights that flash all night to keep the geese from resting overnight on the course. I noticed that the geese still are on the golf course during the day, but they did seem to vacate the area near the lights in the evening. The bad news for us is that I think this might just move them down the valley to our farm. Perhaps we should try some strobe lights and other deterrents as well, because the geese are very noisy at night on our farm.
      There are also public health concerns since Canada geese can contribute to Giardia, Cryptosporidium and Campylobacter outbreaks. As I walk our farm each day checking the new lambs, I can’t help but notice the incredible amount of goose droppings and the effect on our grass growth.
So what can we do? Increasing populations of Canada geese have prompted several communities to control resident flocks. The CRD is currently developing a regional Canada Goose Management Plan because of the effects on our recreational areas, airports and farms. The federal Wildlife Service has produced a handbook for Canada goose management and population control. The handbook has several good suggestions that can be used to discourage Canada Geese through the understanding of their biology. Some methods do not require permits. In the 1970s, the Wildlife Service began to issue permits to property owners whose crops were being ravaged by foraging Canada geese. Some resourceful individuals have killed two birds with one stone, so to speak, by gathering and eating Canada goose eggs. Southern BC allows for more than one hunting season for Canada geese. With resident Canada geese populations growing at a rate of 12% or more per year there will most likely be a peak and leveling off of goose numbers at some point, but not before they go from nuisance to serious problem.

5 comments:

  1. Well it is simply not true Canada geese 'deposit 2-3 lbs. of fecal material. I will also point out their poop is about the same ratio of nitrogen/phosophorus as is in fertilizer farmers buy to spread on their land. So why don't you take advantage of the free fertilizer?

    "A Canada goose does not drop a pound of excrement a day. In a study conducted by Dr. Bruce Manny, research fishery biologist with the U.S. Geological Survey, the average goose produces 0.3432 pounds (5.49 ounces) of wet droppings per day. At 21.04 percent solids in the average goose dropping, this amount of wet droppings is equivalent to 0.0722 pounds (1.15 ounces) of dry droppings per day."

    It is also NOT true their poop is a health hazard unless your immune system is compromised and you chow down on poop that happens to contain pathogens.

    If people worry about geese as a health hazard..they really should look at DOGS and other domestic animals as well as water borne diseases in public swimming pools, water parks, hot tubs, hospitals, and daycares. Then the goose hazard diminishes hugely with some perspective.

    It is my experience that people who whine about geese don't have a lot of facts.

    Environment Canada's Canadian Wildlife Service

    Do goose droppings pose a danger to human health?

    EC-CWS worked with wildlife disease experts at the Canadian Cooperative Wildlife Health Centre to review the diseases carried by and affecting Canada Geese, and their implications for human and animal health. There is no direct evidence that goose droppings pose a danger to human health, and the review concluded that there is not enough data to conduct a meaningful risk assessment. They found large gaps in most of the important factors which are key to determining risk; most importantly, there is virtually no information on the frequency or probability with which pathogens are transmitted from geese to people or livestock. The report is available on CCWHC’s website.

    http://www.ec.gc.ca/mbc-com/default.asp?lang=En&n=98A918B1-1


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    Replies
    1. http://www.aphis.usda.gov/wildlife_damage/nwdp/Publications/10pubs/Swallow%20et%20al%202010.pdf

      According to USDA Wildlife services Canada geese excrete 1-3 lbs of excrement daily.

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  2. According to state and university public health experts including the New Jersey Department of Health, goose feces are fairly innocuous, posing little or no health risks to humans.

    Dr. Timothy Ford, professor at the Harvard School of Public Health and author of "Microbiological Safety of Drinking Water: United States and Global Perspective 1999," states: "Numbers of Cryptosporidium oocysts associated with Canada geese and waterfowl in general are likely to be minimal, unimportant relative to the potential for oocysts shed from other forms of wildlife and humans. IN MY MIND THERE IS NO POSSIBILITY THAT THE CANADA GOOSE WILL EVER BE A MAJOR ROUTE OF INFECTION. TO SUGGEST OTHERWISE IS UTTERLY LUDICROUS AND YOU CAN QUOTE ME

    And David S. Adam, Coordinator of Health Projects, Vector Control, Infectious and Zoonotic Disease Program for the State of New Jersey Department of Health, writes: "Giardia lamblia, as well as Cryptosporidium, is most commonly transmitted to humans by person-to-person fecal-oral contamination or by water fecally contaminated by humans or other mammals. Infection is usually asymptomatic with children infected more frequently than adults, often in the day-care setting. In summary, the role of Canada geese in the transmission of Cryptospordium or Giardia to humans is not well established, BUT APPEARS TO BE SMALL COMPARED WITH OTHER MODES OF TRANSMISSION.”

    Mr. Adams adds that CANADA GEESE HAVE BEEN WRONGLY BLAMED FOR BEACH CLOSINGS: "A number of beach closings including several in New Jersey have been attributed to this cause [high fecal coliform counts attributed to Canada geese]. However, research on this subject (including surveillance conducted in New Jersey) has usually found VERY LOW LEVELS OF PATHOGENIC BACTERIA, such as Salmonella sp., in the feces of waterfowl NOT EXPOSED TO HUMAN SEWAGE EFFLUENT.”

    Dr. Milton Friend, former director, Wildlife Research Center Water Fowl Disease U.S. Fish and Wildlife Service, is adamant: "On occasion we have been wading in that stuff [feces], dead birds up to our elbows... THERE IS NOT A SINGLE DOCUMENTED CASE OF ANY OF US COMING DOWN WITH ANY KIND OF A DISEASE PROBLEMS AS A RESULT OF THE CANADA GOOSE...WE DO NOT HAVE A HUMAN HEALTH SITUATION, NOT IN THE URBAN GOOSE, NOT IN THE WILD GOOSE, and not in the captive geese that we have also worked with. We do have a lot of diseases out there that can affect people. MOST OF THEM COME FROM DIFFERENT PLACES AND DO NOT COME FROM THE CANADA GOOSE AND I’LL LEAVE YOU WITH THAT.”

    Giardia sp., is common throughout the world. The Centers for Disease Control and Prevention (CDC) report that prevalence is higher in areas of poor sanitation and in institutions where children are not toilet-trained. The CDC lists "institutions and day-care centers as the principle mode of spread. " Principle reservoirs are listed as "humans, possibly beaver and domestic animals" -- geese aren't even mentioned.


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  3. MEDIA RELEASE: Egg Addling Controls Goose Population

    “In a continued effort to control the Canada Goose population in the Okanagan Valley, the Okanagan Valley Goose Management Program is about to begin its annual egg addling program. Over the PAST SIX YEARS, this program has prevented the exponential increase of the non-migratory resident goose population that inhabits the valley all year long………Since the program began in 2007, approximately 7,700 EGGS HAVE BEEN PREVENTED FROM HATCHING THROUGH THIS MINIMALLY INVASIVE APPROACH…. ….In order for the program to succeed, new nests need to be identified. The PUBLIC IS ASKED TO REPORT lone geese, pairs of geese or nest locations on private or public land.”

    http://www.okanagangooseplan.com/?p=270

    In addition to ground surveys, aerial surveys were conducted in 2007 and 2011 to estimate the number of geese residing in the Okanagan Valley and to determine what proportion of the population were hatched that year. THE CANADA GOOSE POPULATION APPEARS TO HAVE STABILIZED THROUGHOUT THE VALLEY.

    http://www.okanagangooseplan.com/?cat=6

    GOOSE STRATEGY AND ACTION PLAN.

    http://www.okanagangooseplan.com/files/OVGMP_Strategy_Action%20Plan_2006.pdf

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  4. So, geese are not a health hazard, there are humane effective methods to stabilize and manage their population, and you farmers can buy some herd dogs to protect your crops. Really...at least one third of the food produced gets thrown out in the trash every year anyhow. Protecting your crops with trained dogs should just be part of doing business. The rest of us would like to see our wildlife treated humanely and not all killed for human interests which are a bit out of control these days.

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