The following message about birds and anthropogenic noise was posted on MARMAM,
an E-list for marine mammal research and conservation. Discussion will
apparently occur there, so if you're interested, you may wish to read MARMAM.
--Dave Mellinger, Bioacoustics-L list manager
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Date: Fri, 13 May 2005 10:39:45 -0700
From: Jim Moore <>
Subject: Sound study
I just came across a study of the effects of auto noise on grassland birds in
New England; the authors concluded that traffic noise depressed both presence
and breeding of birds (mainly bobolinks and meadowlarks), with effects measured
1 km from the busiest roads.
Besides being "another taxon heard from", this study has two implicit lessons
for the marine mammals & noise issue.
1) People have been wondering about songbird declines for years, and one
couldn't ask for a simpler system to study noise effects. Yet literature on
this phenomenon appears limited; nobody noticed right under our noses. [NB:
I'm not suggesting bird declines are due to noise effects, just that there's
been a lot of people wondering where the birds are/are not.]
2) Though the data aren't strong on this point, there were indications that
sensitivity to noise (as measured here) varied among grassland species;
obviously, many birds not in this guild appear to have no trouble at all with
auto noise. Noise effects on behavior (in birds at least) appear
species-specific. It would be surprising if they weren't, when one thinks
about it.
I'm not expert in this field and would welcome any discussion on MARMAM about
(a) this and similar studies on birds, and (b) the relevance to marine mammals;
can we consider shipping lanes aquatic versions of country roads and highways?
cheers
Jim
Road traffic and nearby grassland bird patterns in a suburbanizing landscape
Forman RTT, Reineking B, Hersperger AM
ENVIRONMENTAL MANAGEMENT 29 (6): 782-800 JUN 2002
Abstract: An extensive road system with rapidly increasing traffic produces
diverse ecological effects that cover a large land area. Our objective was to
evaluate the effect of roads with different traffic volumes on surrounding
avian distributions, and its importance relative to other variables. Grassland
bird data (5 years) for 84 open patches in an outer suburban/ rural landscape
near Boston were analyzed relative to: distance from roads with 3000-8000 to
>30,000 vehicles/day; open-habitat patch size; area of quality microhabitat
within a patch; adjacent land use: and distance to other open patches.
Grassland bird presence and regular breeding correlated significantly with both
distance from road and habitat patch size. Distance to nearest other open
patch, irrespective of size, was not significant. Similarly, except for one
species, adjacent land use, in this case built area, was not significant. A
light traffic volume of 3000-8000 vehicles/day (local collector street he!
re) had no significant effect on grassland bird distribution. For moderate
traffic of 8000-15,000 (through street), there was no effect on bird presence
although regular breeding was reduced for 400 m from a road. For heavier
traffic of 15,000-30,000 (two-lane highway), both bird presence and breeding
were decreased for 700 m. For a heavy traffic volume of 30,000 vehicles/day
(multilane highway), bird presence and breeding were reduced for 1200 m from a
road. The results suggest that avian studies and long-term surveys near busy
roads may be strongly affected by traffic volume or changes in volume. We
conclude that road ecology, especially the effects extending outward > 100 m
from roads with traffic, is a sine qua non for effective land-use and
transportation policy.
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