Discussion
After examining all of our data, we have come to the
conclusion that the Canadian geese population has decreased in zone 2 during the
summer months of June, July and August in 2006, which supports our hypothesis.
The vegetation buffer may have some impact as to where the geese tend to reside.
It appears that the geese may be gathering in other zones that do not have the
vegetation buffer along the water’s edge, as we predicted. It is known that
geese like to be near water, so they can have an escape route from predators.
Based on our results, we believe that the decrease in the time frame from May
1st – June 5th between 2004 and 2005 may be due to the fact that the planting of
the native vegetation along the shoreline of zone 2 was taking place. The geese
may have avoided that area due to all of the activity and the people. The
increase, from May 1st – June 5th from 2005 to 2006 was most likely due to the
fact that the buffer had not started to grow back up yet so the geese still had
a straight path to the water. Also, this may be a prime spot for the geese to
lay eggs because the short vegetation is thicker than the normal grass. Nests
are also generally near water, as the water provides access to food, a place to
drink, and an escape route from predators. The adult geese without goslings or
eggs are also likely to be in the area of zone 2 due to the low vegetation.
During the time period from June 6th – July 6th, we saw a continuous decrease in
the percent of geese observed in zone 2 from 2004 to 2005 and then again from
2005 to 2006. This may be because the vegetation during this time period is
between 1 and 2 feet high. This may be high enough to block the geese’ path to
the water, so they may choose a different area around the body of water to
reside in.
July 7th – August 31st from 2004 (when there was no buffer) to 2005 (when there
was a buffer with a gap), the percentage of geese in zone 2 stayed relatively
the same, while from 2005 to 2006, it decreased, most likely due to the full
buffer. At this time it is also at its maximum height and thickness, obstructing
the geese’s view of the water. Also, beginning around early July, adult geese
and goslings begin to fly, allowing them to be mobile and move to other zones
where they can get a better view of the water
(FIGURE 2).
Each year, from 2004 to 2005 to 2006, there is a decrease in the percentage of
geese in zone 2 compared to the rest of the zones. The percentage has
increased over the years in zones 1, 4, 5, and 6
(FIGURE 2). In these zones
there is no vegetation buffer, so the geese appear to be congregating in these
areas.
Although we were able to find evidence to support our hypothesis, we found various sources of error that could have potential effects on our data. There was a lack of observations recorded for each month. Some months had no observations. This made it difficult to test our hypothesis. Another source of error could have been the recorder of the information in the Excel Spreadsheet. How accurate was the information recorded, and how accurate and reliable are the data collected by past groups? Did they count any of the geese twice, or did they miss some of the geese? Also, unpredictability of weather has an effect on breeding, molting, and vegetation growth of the geese.
We found information on the Department of Natural Science website (2003-2004
student goose study) that came to the same conclusion. In areas where certain
obstacles are blocking bodies of water, geese populations tend to be very small
or even nonexistent. This is simply because it is blocking their paths to their
escape route from predators.
From our data, it appears that there is a decrease from 2005-2006 from the beginning of June to the end of August. Because of this, we support extending the vegetation buffer throughout all of zone 1. Then, the geese will have no reason to go into zone 2. It is a possibility that they are coming out of the water from zone 1 and walking over to zone 2 that way. Adding a full buffer to zone 1 and taking more observations or counts of geese would allow a better test of our hypothesis.