LOCKPORT - DNA test results on the bacteria that sometimes cause the closure of Krull Park beach in Olcott have blown a hole in the theory that seagull droppings caked on nearby piers were to blame.
Niagara County Enviromental Health Director James J. Devald disclosed Thursday that analysis of bacteria gathered from the waters of Lake Ontario Aug. 6 showed the e. coli in question came from ruminants - animals that chew their cuds.
"No gulls, no geese, no humans," Devald said.
He said the source of the e. coli, a bacteria found in the guts of warm-blooded animals, could have been cows, deer, sheep or goats.
"That came back as a surprise to us," Devald said. but the results were confirmed by multiple technicians at the state Health Department's Wadsworth Laboratory in Albany, who worked independently and came up with the same results.
Three samples were taken, one at the mouth of Eighteen Mile Creek and two right off the beach, which is to the east of the creek. The current in the lake takes the creek water toward the beach, passing two long federally owned piers that are liberally coated with bird poop.
The DNA testing was ordered after Krull Park Beach was closed to swimming eight times in the summer of 2011, for a total of 20 days.
Last year, sampling ruled out the notion that discharges into the creek from the City of Lockport wastewater treatment plant, 13 miles from the lake, could have been to blame.
Tests taken in several different locations between Lockport and Olcott showed the e. coli levels steadily dropped between the sewage plant and the creek mouth, before rising again between the creek and the beach.
This season, which was far drier than last year, the beach was closed only three times for a total of seven days.
Public Health Director Daniel J. Stapleton said when the water is warmer, the bacteria levels increase.
On all three occasions when the beach was shut, the wind was blowing at more than 10 mph from the north, making Devald wonder if the water hitting the beach was rousing up bacteria hiding in the sand or seaweed.
Samples of beach sediment are being taken next week, with results expected in October.
Agricultural runoff into the creek could be a possible e. coli source, Devald said, but the large farms with animals aren't located along the creek, but farther east.
Stapleton commented, "Being such a hot, dry summer, the chances of runoff are reduced."
The scientific work will continue at the beach in 2013 as the hunt for the source of the bacteria continues. "This will be a 100 percent data-driven experiment," Stapleton said.