A local population of the endangered Banff Springs snail – believed to have been completely wiped out earlier this year – has been found alive and well.
And, on top of that, two new snail populations have been discovered on the slopes of Sulphur Mountain in Banff, although it has not yet been verified they are they the same species of snail.
The endangered snails in Kidney Spring were thought to have been extirpated when the thermal water in which they survive stopped running last spring for up to 12 weeks.
But in a surprising discovery, scientists spotted some living snails in Kidney Spring in early July and counted as many as 142 snails late last week.
“Scientists don’t like to be wrong, and while I wasn’t wrong with my predictions of the springs drying, I was wrong about their survival,” said snail expert Dwayne Lepitzki.
“We think the springs dried between eight and 12 weeks and somehow, someway, they did survive the drying event and that’s really good news and I’m happy to be wrong about that.”
Kidney Spring is one of seven thermal springs on Sulphur Mountain in which the lemon seed-sized Banff Springs snail exists in the entire world.
But two other sites near existing populations – one 10 metres away and the other about 40 metres away – now also have been found to contain snails.
Parks Canada plans to do genetic work to determine if they are, in fact, the same species of endangered snail, known scientifically as Physella johnsoni.
No one knows for sure how the snails got into the two new locations, but there are theories they were transplanted by birds, rodents or even hopped a ride on the hoof of an elk.
Lepitzki has also seen a snail on the back of a wood frog, but emphasises this is a possible mode of transport for freshwater snails for very short distances only.
“If they are Physella johnsoni, and if they got there naturally, then it’s good news,” said Lepitzki.
Meanwhile, Kidney Spring ran completely dry for more than two months this past spring, but a trickle of water resumed flowing mid-May.
Lepitzki said there were no signs of any surviving snails in two separate surveys after the water flows resumed, but then six snails were found alive on July 8, 32 on Aug. 5 and 142 on Sept. 2.
“The population is growing,” said Lepitzki, who has been on contract with Parks Canada since the fall of 1995 to study the snail.
“Typically, the fall is when the populations start increasing again. We think it has to do with the food source.”
Bill Hunt, resource conservation manager for Banff National Park, said the survival of the snails in Kidney Spring is “terrific news”.
“They must have been able to survive the drying by either moving back down a vent into the source of the spring or finding wetted habitats further back where they were out of view,” he said.
“They were without water for 10 to 12 weeks and able to persist throughout that and they’re now doing well. The habitat looks great, algal mats have recovered, the pools are nice and deep.”
Hunt said the next step for Parks Canada involves coming up with a strong emergency response plan in the event Kidney Spring runs dry again.
As well as genetic work on the two newly-discovered populations, he said they also plan to do additional DNA analysis on the existing seven Banff springs snail populations.
Hunt said they would work with DNA experts to try to use snail feces or slime to do the genetic testing, but if that’s not possible, they hope to collect about 20 snails when the populations peak in winter.
“The goal of the genetic work will be to better understand how related the populations of the Banff Springs snail are, and that way we’ll have a better understanding of what is at risk,” he said.
Once they have that information, Parks Canada will be in a better position to make important decisions, like whether to let an existing population die out, and then re-populate, should flows stop again, or mount an emergency rescue and store the stranded snails elsewhere.
Last spring, one of the problems was there was no emergency plan in place – despite predictions the springs would cease flowing – and Parks decided against intervening and rescuing the snails.
Parks indicated they had reservations about reintroducing the snails back into Kidney Spring only to have the pool run dry again next year.
Hunt said the genetic analysis will help with decision-making, adding “we don’t want to end up in the dilemma we were in last spring. We’re really looking forward to working our way through the genetic analysis so we can come up with a better, more rigorous emergency plan.
“We take the recovery of the species very seriously and look forward to having better information so we can use our resources as efficiently as possible.”
Hunt said finding snails in two other locations is “another good news story”.
“Until we do genetic work, we can’t confirm if they’re true Physella johnsoni. They look pretty similar, but we have to be sure,” he said.
“There is another Physella (known as Physella gyrina or common tadpole snail) that we find at Vermilion Lakes and it could potentially be that kind.”
Lepitzki said the environment in which the two new populations have been discovered is somewhat different, noting they are cooler waters.
He said Kidney Spring and Middle Springs are presently running around 36 C. The water at one of the new sites is 32 C, which is considered reasonable, while the other is 28 C.
“Because the water is so much cooler, the bacteria looks completely different,” he said.
If these snails do in fact turn out to be the endangered Banff Springs snail, Parks Canada officials say it’s good news for the population as a whole.
According to the recovery plan for the Banff Springs snail, the biggest threat to the survival and persistence of this endangered species is the stoppage of the springs.
“The more sites where we can have snails occupying springs or outflow areas, the better the chances of survival for the overall population,” said Hunt.
“If we can put our eggs into as many baskets as possible, that helps the population be more resilient to drying events and it helps ensure the longevity as a species.”
The population in Kidney Spring was reintroduced in November 2003 and has thrived since then. The year before that was the only other known time that spring ran empty.
What used to be a rare occurrence of springs drying up along the Sulphur Mountain thrust fault – located slightly to the west of the the Banff townsite and running along the east-facing slope of Sulphur Mountain – is becoming more and more common.
The Upper Hot Springs has run dry 12 times in the last 15 years, typically in late winter and early spring. The popular tourist attraction is supplemented with tap water when this happens.
The only other documented times the Upper Hot Springs experienced low flows or completely stopped flowing were in 1970 and 1923.
While many theories abound on the reasons for the stoppages, some scientists believe recent flow anomalies in the springs are ultimately caused by climate change.
Meanwhile, Parks is coming up on the five-year review of the recovery plan for the Banff Springs snail and will report on what initiatives are working and those that are not.
It is listed as an endangered species and is more at risk of going extinct than grizzly bears in Banff National Park. The snail is legally protected under the Species At Risk Act.
Hunt said the ultimate goal would be to get the Banff springs snail off the endangered species list.
“It would be an historic moment,” he said.
Until the spring of 2010, the Banff Springs snail was the only species in Banff National Park that was endangered, meaning the most at risk of going extinct.
But in April 2010, the Committee of the Status of Endangered Wildlife in Canada (COSEWIC) assessed the whitebark pine as endangered. This tree grows at high elevations in the mountains of B.C. and Alberta, including Banff.
