door county avian waste survey and bird count colleen mcdermott, d.v.m., ph.d. university of...
DESCRIPTION
Door County While all sources are possible, avian waste has been suggested as important source Large numbers of gulls and geese at some beaches –E.g. Whitefish Dunes & gulls –E.g. Otumba Park & GeeseTRANSCRIPT
Door County Avian Waste Survey
and Bird Count
Colleen McDermott, D.V.M., Ph.D.University of Wisconsin Oshkosh
Oshkosh, WI 54901Phone: (920) 424-1102FAX: (920) 424-1101
Sources of E. coli at Recreational
Beaches• Human waste• Agricultural runoff• Domestic pets• Avian waste
– Gulls– Ducks– Geese– Others
Door County
• While all sources are possible, avian waste has been suggested as important source
• Large numbers of gulls and geese at some beaches– E.g. Whitefish Dunes & gulls– E.g. Otumba Park & Geese
Avian Waste
• Contains:– 3.7 X 108 fecal coliforms/gram feces (Alderisio &
DeLuca, 1999)– E. coli (indicator organism of fecal contamination)
-Potential pathogens• Salmonella• Campylobacter
– Avian waste as source of E. coli may have lower potential to cause disease in humans than other sources
Ways to ID Source of Contamination
• Many have been suggested– DNA fingerprinting (E. coli & other fecal organisms)– Antibiotic Sensitivity Profiles– Caffeine concentrations– Etc.
• None are easy or definitive• Often bird counts at beaches have been used to
determine impact of avians on beach health– Once/day snapshot count– Longer term counts
Other Ideas?
• Quantify amount of avian waste on beaches, rather than bird numbers
• Summer 2004– Counted and classified avian waste “droppings”– 10 Beaches in Door County– Each beach was counted 1X/week for 14
weeks– Used random grid counting method
Method
• Sampler throws square grid (1.5 m2) in transect zone along swash zone
• Counts waste within grid and classifies type of bird waste
• Moves to next location 45.5 m along swash zone
• Throws grid again and counts• Repeats for a total of 9 sampling plots
Figure 1: Sampling scheme for avian waste enumeration (Fish Creek, WI)
40
14
23
5
149
12
57
10
21
97
0
20
40
60
80
100
120
Avi
an W
aste
Cou
nt/b
each
/day
13 15
27
5 7 4 5
26
410
90
0
10
20
30
40
50
60
70
80
90
100
Baileys H
arbor
Egg Harb
or
Ellison Bay
Ephriam
Fish C
reek
Newport
Otumba
Portage
Sister
Bay
Sunset
White
fish D
unes
Bir
ds/b
each
/day
Table 1: Pearson Correlations for Avian Waste and Bird Counts with E. coli
Beach
Avian Waste vs.
Bird Counts
Avian Waste vs.
Bird Counts: p-value
Avian Waste vs.
E.coli
Avian Waste vs. E.coli : p-
value
Bird Count vs.
E.coli
Bird Count vs.
E.coli: p-value
Baileys Harbor 0.138 0.745 -0.365 0.374 -0.434 0.282Egg Harbor -0.191 0.574 0.521 0.100 -0.149 0.662Ellison Bay 0.063 0.871 0.043 0.913 0.880 0.002Ephraim 0.563 0.090 -0.135 0.711 -0.117 0.748Fish Creek 0.000 1.000 -0.216 0.524 -0.057 0.868Newport 0.853 0.003 -0.166 0.670 -0.036 0.927Otumba 0.229 0.474 -0.184 0.567 0.695 0.012Sister Bay 0.103 0.778 -0.008 0.982 0.478 0.162Sunset -0.255 0.424 0.505 0.094 -0.045 0.891Whitefish Dunes 0.129 0.397 -0.172 0.259 0.345 0.020
Table 1: Proportions of bird types in Door County, WI Summer 2004
Beach Gulls as percent of total birds present
Geese as percent of total birds present
Mean log10 E. coli concentration
Baileys Harbor 78% 21% 1.44
Egg Harbor 53% 43% 1.45
Ellison Bay 41% 27% 1.65
Ephraim 61% 27% 1.05
Fish Creek 36% 30% 1.58
Newport 88% 4% 0.79
Otumba 18% 73% 1.68
Sister Bay 67% 7% 1.30
Sunset 78% 18% 1.79
Whitefish Dunes 100% 0% 1.17
Summary
• Avian waste counts do not correlate with bird numbers nor with E. coli concentration in beach water
• At a few beaches bird counts do correlate with E. coli concentrations in beach water
• Proportions of gulls vs. geese does not seem to affect E. coli concentrations in beach water
Future Work
• In Summer 2005 we will expand project– Count avian waste and bird numbers at 13
beaches in Door County– Add numbers to ensure our statistics are
powerful– Continue to collect avian waste samples for E.
coli isolations, DNA fingerprinting, antibiotics sensitivity profiles
Thank you
Questions?