Add Category
In early August each year, Adam Hardy from Raptor Care North West starts feeling nervous for Tasmania's peregrine falcons, which always nest on cliffs.
"Peregrines in Tasmania generally breed from late August through to, say Christmas time," he says.
Across the state, Mr Hardy estimates up to 30 peregrine falcon nests are located on cliffs where there are established rock climbing routes.
"And it's rock climbers and peregrines being in the same place at the same time that causes mishaps," he says.
He says if a rock climber climbs near a falcon nest, the parent birds will spend time away from their eggs or young to fend them off.
Offspring left alone for extended periods have their survival jeopardised, mainly through exposure to the elements.
"It only takes half an hour in bad weather … for things to go pear-shaped," Mr Hardy says.
"And that's the whole [breeding] season gone for those birds."
Plight of the peregrine
Peregrine falcons, the fastest animals on Earth, are found on every continent except Antarctica.
Mr Hardy says the Tasmanian population is estimated to number about 650, including 150 to 200 breeding pairs.
He says breeding females typically lay three eggs each year, in late August or early September, and chicks usually fledge in December.
Peregrine falcon chicks have a naturally low chance of survival, with most dying in their first year.
Adding to naturally occurring pressures on the species are those imposed by humans, Mr Hardy says.
He says peregrines in Tasmania have historically been "massively persecuted', which led to them sitting on the threatened species list for many years.
Pigeon racers targeted peregrines in the 1930s because they sometimes preyed on pigeons, and the use of organochlorine pesticides from the 1960s to the 1980s thinned their eggshells, which led to increased mortality of unhatched chicks.
"So they've faced a lot of pressure, and any more pressure that we that we put on them is just going to turn the clock back once again," Mr Hardy said.
Falcons and people vying for cliffs
Mr Hardy says he has seen peregrine falcon nests on cliffs ranging from 10 to 200 metres high in a "broad range of places" in Tasmania.
He says the birds always choose a nesting site within 3 to 4 kilometres of a reliable food source, and prefer isolated locations where they will not be bothered.
"Most of these sites are in a beautiful situation in beautiful habitat, and people like those kinds of places [too]," Mr Hardy says.
He says bushwalkers, photographers and people building houses near cliffs all pose a potential problem for nesting falcons.
"[But] I guess climbers present more of a hazard because … they're on the cliff, and they're heading up the cliff," Mr Hardy says.
This is particularly the case if they come too close to a parent falcon's nest, with even a distance of 200m to 300m enough to disturb the birds.
"Once someone's halfway up a cliff, or particularly if they're above it, the parent falcons can come off [their nest]," Mr Hardy says.
"They get very aggressive and they'll start dive-bombing the climber there.
"[And] if they’re off swooping characters that are climbing all over their cliff, they’re compromising their youngsters or their eggs."
Mr Hardy says peregrines are notoriously persistent in their swooping, while climbers can spend hours at a cliff they are climbing.
This means falcon eggs and chicks can be left unattended for extended periods, increasing their risk of death due to exposure or predation.
"It only takes one person to be in the wrong spot at the wrong time, and be there for a little bit too long, for the birds' whole breeding season to be messed up," Mr Hardy says.
If breeding is interrupted "in a few different locations" then it risks "a dramatic drop in the population and they're heading in the same direction they were 40 years ago".
Life and near-death on cliffs
Mr Hardy says peregrine falcons often return to existing nests year after year, sometimes for thousands of years running.
When a peregrine falcon nest on Hunter Island, north-west of Tasmania, was radiocarbon dated in the 1980s, it was found to be 19,600 years old.
"That's the oldest bird nest ever recorded in the world … so there's a massive history there," Mr Hardy says.
"That's essentially 20,000 years of [repeated] occupation at one site by these birds, which is just mind-blowing."
There would be dozens of nests of a similar age across Tasmania, Mr Hardy estimates, many of which had climbing routes established near them over the last few decades.
Climbing away from the past
Climb Tasmania president Gerry Narkowicz says many routes were established 30 years ago when climbers were "ignorant of raptors and their nesting habits".
"Back in the day, I'm talking 40 years ago, we'd go climbing at crags with falcons … and we'd just go in September and not worry about it," he says.
He describes an occasion when he was continuously swooped by a falcon, which eventually hit him.
"It came screeching past and hit me on the shoulder. It scared the s**t out of me and nearly knocked me off the cliff," Mr Narkowicz says.
These days, he says, the Tasmanian climbing community is not only well informed about falcons, but actively working to stay out of their way.
Mr Narkowicz listed falcon sites in his "go-to guide" for rock climbing in Tasmania, and advises people to "avoid nesting seasons between August and December at these areas".
He says most climbers also visited Climbers Club of Tasmania or Launceston Rock Climbers Facebook pages.
Posts on these pages, and on Thesarvo, a mountain sports blog site, state where known falcon nests are, ask for information about newly discovered nests, and advise followers to stay away from all active nests in the breeding season.
The Crag Care Tasmania website, an organisation comprising volunteer, conservation-focused rock climbers, also provides information for climbers about nesting raptors, with the group's Nick Morgan saying it also created educational posters.
Mr Narkowicz says every climber he knows is not only well-informed about falcons, but wants to "do the right thing" by the birds.
"Climbers, I would say, are one of the most environmentally friendly … user groups in the bush," he says.
"[We] are extremely respectful because, on the whole, we love the wilderness and we want to … preserve it for future generations."
Thanks in advance
Mr Hardy believes it was probably visitors to the state, rather than members of the Tasmanian climbing community, who had caused problems for breeding falcons in recent years.
He has witnessed two occasions where climbers getting swooped by falcons persisted with ascending the cliff regardless.
"It's a little bit frustrating when you get the bad seeds that do the wrong thing and mess it up for the others," Mr Hardy says.
He did not think the problem for falcons would "go away in a hurry", especially given the current expansion of extreme sports, and the ever-increasing number of people "chasing beautiful things".
But he thinks praising people in advance for avoiding falcon nests during the breeding season can help the birds' offspring at least survive their first few months.
Mr Hardy adds that he is "incredibly thankful" to people who respect the space of breeding falcons in Tasmania, because they are partly the reason the peregrine population in the state can keep "ticking over".