Are anglers leaving behind toxic lead?

Fishing sinkers, jigs looked at as possible cause of avian deaths

Highly toxic lead sinkers and jigs used by increasing numbers of anglers in Hamilton Harbour could be an explanation for a recent spate of lead poisonings of swan and juvenile bald eagles.

“Logic would have you take a good strong look at that because things have been so quiet with no lead for a while and then all of a sudden there is a lot all at once,” says Bev Kingdon, of the Trumpeter Swan Restoration Group, a volunteer organization that keeps an eye on swans at LaSalle Park among other places.

Five dead swans recently picked up by Hamilton Animal Services near Hamilton Harbour are undergoing

testing for lead poisoning, part of a list of troubling local avian deaths that include two juvenile bald eagles.

One of the eagles was found in Cootes Paradise, the other in Christie Conservation Area.

Both were in distress and later died. One tested positive for lead poisoning, the other still has to undergo testing.

As well, at least four other ill swans are being treated for lead poisoning

at different wildlife rescue centres in the area.

Walleye stocked in the harbour by the Ministry of Natural Resources in recent years have matured, turning the waterway into a favoured fishing spot.

“There has been a resurgence in interest which has attracted additional anglers to the area,” says angler Ben Gottfried “The word walleye ... has attracted the attention of fishers from near and far, some I’ve spoken to have driven nearly 100 kilometres to see what the buzz is about.”

But an unknown number of anglers have undoubtedly left lead sinkers and jigs behind that can be ingested by birds and other wildlife.

According to an Environment and Climate Change Canada notice from May of last year, “An average Canadian angler can lose 11 to 15 jigs and sinkers per year while fishing due to snags and other reasons. This adds up to about 460 tonnes of lead jigs and sinkers lost every year into Canada’s lakes and waterways. This represents the most significant source of lead releases into Canadian waters.”

Trumpeter swan restoration group members regularly bring dead birds to the University of Guelph for lead testing, something that can take several months.

Since the early 1990s, some 80 dead swans have tested positive for high levels of lead poisoning, says Kingdon.

Lead sinkers and jigs are banned from national parks and wildlife areas, but Hamilton Harbour is not classified as either.

Gottfried says lead sinkers are preferred by anglers over alternatives on the market because “of the properties of lead. Lead is soft and may be less prone to damaging the line ... Lead is also very heavy for its size, something that is important in various applications of fishing.

“Lead is also relatively affordable and readily accessible.”

Another big factor in causing lead poisoning in birds is lead shot used by hunters. Lead shot is illegal for hunting migratory game birds but is still permitted in other kinds of hunting and target shooting.

Hunting is not permitted in Hamilton harbour, but birds that nest around the bay could be ingesting lead shot while looking for food elsewhere. Bald eagles and swans can fly great distances.

“Lead poisoning can occur in scavenging birds such as raptors, vultures, crows and ravens that ingest lead ammunition while feeding on carcasses of hunted game,” says Environment Canada research scientist John Chételat.

The Ottawa-based scientist is heading up a multi-year national study that began last year to “generate information on the extent of secondary lead poisoning in scavenging birds across Canada,” he says.

“We are working with a variety of collaborators in each province to obtain tissues from carcasses for lead analysis, and we will be compiling a national database of new and historical data on lead concentrations in scavenging birds,” he says.

Currently, he says, there is a lack of data to assess the scope of the problem in Canada. The hope is to identify bird species that are most vulnerable and identify locations that pose the most risk.

Birds that have died in Hamilton Harbour will be part of the national study and the results will be of major interest for stakeholders involved in the restoration of the bay.

In addition, the Hamilton Harbour Remedial Action Plan technical team is studying the recent spike in swan and eagle deaths.