Disturbance at the Fill

Stuart MacKay stuart at blarg.net
Tue Mar 5 15:30:41 PST 2002

I read with interest Melissa Keigley's posting about disturbance at the

First I should point out that I regularly go "off-trail" to bird watch -
usually I follow the unofficial trails. While some disturbance to birds
undoubtedly results I would like to point out some additional sources of
disturbance - not just to assuage my guilt:

1. Dogs - on and off leash. I do not have the figures but anecdotal
evidence suggests that the numbers of wildfowl found on the ponds are a
fraction of what they were before dogs were encouraged into the area.
Keeping dogs leashed and on the path does not change anything - the path
runs close to all of the ponds (except the tree-lined one, north of
Waikiakum Lane). I have frequently seen birds fly from the central pond
when sighting a dog being walked along the path.

2. Joggers, particularly late evening and at night. There are a
surprising number of people walking around the Fill at night. a lot of
wildfowl used to congregate on the ponds but are often disturbed by
people running around the area.

3. The large number of people using the area. Since the paths are
regularly maintained the numbers of people using the Fill for recreation
(non-birding) has increased enormously. This results in increased
disturbance by default.

4. Predators - not just the dreaded 'c' - word. Crows and rats are
probably the most significant causes of nest failure in songbirds. As an
example there are usually 2-3 pairs of Kildeer nesting in the area and
to the best of my knowledge the number of chicks fledging in the past 5
years or so can be counted on one hand with a few fingers left over.

5. Mowing of the blackberry. This occurs regularly that vegetation fails
to develop so large areas of the Fill are left looking like lawns. I'm
not sure what the solution to this is but leaving the blackberry alone
is one. The policy of blackberry removal has resulted in numbers of
sparrows and warblers being reduced considerably though again the
evidence is anecdotal rather than scientific.

I am not sure where birders would come on this list in terms of amount
of disturbance caused.

On the last point I should state that I used to be an avid advocate of
removing all non-natives so that the area was returned to something
close to the grassy meadow that was so successful in attracting
shorebirds in the 1970's and 1980's before trees, blackberry and
loosestrife took hold. With the current state of the Fill I will be more
careful in what I wish for in future.

Stuart MacKay, Seattle, WA
stuart at blarg.net

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