RESIDENT CANADA GOOSE POPULATION ESTIMATE
This year, for the first time since 1997, MassWildlife biologists made an attempt to estimate the number of Canada geese living in Massachusetts. The estimate was calculated by neck collaring a sample of geese captured during normal summer round-ups to band molting adult birds and pre-flying goslings; then looking for those collars while counting all the geese observed in August after the molt was over and geese were able to fly and disperse around the state.
Using yellow plastic neck collars with black codes, geese were marked at 188 sites across the state in 120 towns and cities during June and July. In August, MassWildlife personnel fanned out across the state with spotting scopes, looking for resident geese before the special September hunting season opened for these birds.
The study started with a data base of 470 collar codes, including 13 previously collared geese recaptured during summer round-ups. Combining all of the observations made by MassWildlife personnel with a few reliable reports from the public, then eliminating some duplicate coverage, 15,810 geese on 502 sites were examined for neck collars.
There were 195 geese recorded with collars; 1 collar for every 81 geese. After adjusting for collars reported more than once, it was determined that 13,542 individual geese had been observed. There were 167 unique collar codes (which included some not in the data base).
Comparing these codes against the data base, MassWildlife Waterfowl Project leader H W Heusmann determined that 34.3% of the collars that been re-observed, and so concluded that 34.3% of the geese in the state had been counted. A simple algebraic formula gives a population estimate of 39,481 geese in the state prior to the opening of the 2005 September goose hunting season. The actual figure is probably over 40,000, as the count did not include Nantucket or Martha’s Vineyard which also have resident Canada geese. This compares to the last population estimate of 38,000 in 1997, a period when the regular Canada goose hunting season had been closed the previous two years. The first Massachusetts goose population estimate based on this technique in 1991 had indicated a population of 26,000 geese. Heusmann believes there were likely 6,000 to 8,000 resident geese in the state when he began as project leader in 1970.
MassWildlife biologist Tom Early pointed out that while we currently are observing geese on many areas, the individual flock sizes tend to be much smaller than they were during the 1990s. Only 29 of the 502 observations (6%) involved flocks of a hundred or more birds. The only really large flocks were on the Connecticut River in Longmeadow (520); D.W. Field Park in Brockton (518); Great Meadows NWR (324), Concord; Acoaxet Country Club, Westport (284); Brookfield Rd, Charlton (245); Bowens Lane, Rochester (204); Somerset Reservoir, Somerset (203); and Charles River, Cambridge (200). A third of the observed flocks consisted of 10 or fewer birds.
Examining the data on less than a statewide level increases the chances for error, but Heusmann did so out of curiosity. He discovered that the data suggested there were over 8,100 geese in the metro area of Boston within Rt. 128 from Nahant to Hull. In contrast, there were only 8,300 geese in all of Massachusetts from Worcester County and west. Heusmann believes that hunting plays a large role in holding the population in check in the western half of Massachusetts, but municipal restrictions on hunting in eastern Massachusetts, especially around Boston, allow populations to increase to high levels. Because of the many complaints about Canada geese, Massachusetts has (in addition to the traditional waterfowl hunting season) two special hunting seasons to reduce the numbers of resident geese. A statewide September season runs from the day after Labor Day to September 25 with a 5 bird daily bag limit. The season is timed to occur before migrant geese begin moving south into the Commonwealth. There is also a late season that runs from Jan. 16 to Feb. 15 in the Central waterfowl hunting zone, and from Jan 23 to Feb. 15 in the North Coastal zone, both with a daily bag limit of 5. The late season is designed to harvest Massachusetts geese after the southbound migrant geese have passed through the state. During the regular waterfowl season the daily bag is 3 in the Berkshire zone and 2 in the Central and Coastal zones.
Click Here To Return To The Previous Page
