Wildlife
Shark tales: Canada’s great whites
As white sharks make their presence known off the coast of Atlantic Canada, researchers and locals want to know: should people be worried?
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A new wildlife experience is coming to Liverpool, Nova Scotia, and it’s quite a thriller. Cue up the Jaws theme, because starting in August, Nova Scotians will be able to go cage diving with great white sharks. Atlantic Shark Expeditions, headed by Niel Hammerschlag, a marine biologist who has worked with sharks for over 25 years, will be running daily expeditions on the south shore of the province from August 1 to the end of October.
In addition to shark adventures, he will also be using the expeditions to conduct research on the sharks to learn more about the changing population, and how both climate change and human activity influence the great whites. This research will include tagging the sharks and building a database, as well as conducting biopsies and ultrasounds on the sharks as they swim. Great white sharks are an endangered species globally, and the coast of Nova Scotia could be a stronghold for them, Hammerschlag said.
“It’s really important to figure out what makes them tick so we can make sure we can protect that to support their recovery,” he told CBC.
Humans aren’t the only species who fight with their siblings, but for one species, sibling rivalries have much higher consequences. Sibling rivalries in Canada jays have lifetime benefits for the dominant juvenile, but potentially deadly consequences for the others.
Canada jay fledglings fight with their siblings when they are just six weeks old. The winner of the fight, or the “family bully,” forces the other fledglings to leave the territory and remains in the nest with its parents for a year. Those that were forced to flee must find another home territory or join an unrelated pair of Canada jays nearby. Banished jays have a mortality rate of 80 per cent in their first year, as they often die of starvation or predation.
Researchers in the College of Biological Science at the University of Guelph examined 58 years of data on Canada jays in Algonquin Park. They found that dominant juveniles were more likely to reach adulthood and reproduce if they forced their siblings out of the nest as fledglings.
The number of occupied jay territories in Algonquin Provincial Park has fallen approximately 75 per cent compared to record highs. Therefore, understanding Canada jay behaviour is becoming increasingly important as climate change threatens their populations.
Recent reintroduction efforts by the Wilder Institute have given critically imperiled northern leopard frogs in B.C. new hope. Currently, only one population of northern leopard frogs remains in the province, due to habitat loss, invasive species and disease.
However, the species is showing early signs of success at a new reintroduction site in Cherry Meadows Conservation Area and Sparrowhawk Farm wetland complex in B.C. Their survival rate from tadpole to young-of-year frogs was higher than other true frogs and young-of-year frogs have reached sizes expected of a two-year-old northern leopard frog.
Researchers plan to return to the site in the summer to determine how many frogs have survived the winter. During winter, northern leopard frogs are particularly vulnerable to predators and disease and only 10 per cent survive their first year of winter.
When choosing this reintroduction site researchers ensured that waterbodies in the wetland had ideal temperatures and dissolved oxygen levels for winter survival. If the rate of overwinter survival is promising and there is evidence of breeding in the wild, these efforts may result in the successful establishment of a second population of northern leopard frogs in B.C.
The Prairie Pothole Region of North America has been the traditional breeding grounds of approximately 10 million waterfowl, for thousands of years. The landscape of the region, which spans parts of Southern Alberta, Saskatchewan, and Manitoba, has changed significantly due to weather patterns and agricultural practices. This evolving landscape has impacted waterfowl breeding, with some populations proliferating while others decline.
A new study led by a Pennsylvania State University research team found that when waterfowl nest is a key factor in determining the success of a population. Early-nesting ducks face increased risk due to changes in climate and land use.
When early nesting ducks arrive, many fields are covered in leftover debris from the previous harvest, primarily stubble from cereal grains. While the stubble looks good from the air, it doesn’t offer the same protections. The eventual replanting of these fields often results in agricultural activities destroying their nests. This leaves the ducks vulnerable to predators and leads to lower reproductive success.
These findings will help future targeting efforts for waterfowl species of concern and areas of conservation priority.
Pokémon Go meets wildlife in a new game, created by an Ontario woman, Natalie Rudkins. She designed and compiled a ‘Naturedex’, of 151 species of wildlife including birds, insects, flowers, and trees that can all be found in the Toronto area, to create a similar version of the popular game that involves nature.
Whereas Pokémon Go involves finding virtual creatures, this Naturedex is full of real wildlife that people are around daily. She posted the Naturedex to Reddit, where it sparked a lot of interest, especially among families and other nature enthusiasts.
Rudkins told CBC that she hopes the game teaches people more about the natural world all around them.
Each species on the deck has a rating between one and three based on how difficult they are to find. While Rudkins only found 120 herself last year, she hopes that someone will “see ‘em all” before the end of the year.
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