“I’ve photographed at least a dozen species, and have seen that many more recorded by other divers. Some
species seem to arrive as juveniles like the butterfly fish and band tail puffer [about the size of a penny]
while others seem to be fully mature.”
Mr Bond said he also noticed changes in local species such as the wolf eel, which was reasonably common
but now he spots it just once a year at most.
According to data collected by Fisheries and Oceans Canada, ocean temperatures started to sharply climb in
2010.
Dr Bryce Stewart from the University of York said marine species do occasionally end up well outside their
normal ranges, especially if they get caught up in currents or storms, but this is happening more and more.
“That is partly because more people are out there in and on the oceans these days, and social media makes
sharing unusual sightings much easier than in the past,” he said. “But overall there is no doubt that many
marine species are changing their ranges, moving away from equator towards the poles as the water
warms.”
Monitoring programmes around the UK show that we are increasingly seeing Mediterranean species in UK
waters.
“There will be winners and losers in the ocean as it continues to warm with climate change. But overall
biodiversity is expected to decline. There is also the threat of invasive species and diseases causing damage
to existing species and habitats when they move to new areas,” said Dr Stewart.
Last month the planet’s most northerly human settlement – Alert, in Nunavut – experienced an
“unprecedented” heatwave. Canada’s weather agency confirmed that temperatures peaked at 21C – far
exceeding the July average for the area of around 5C.
If serious action is not taken by world governments to cut global greenhouse gas emissions, ocean
temperatures are likely to rise by up to 3.2C by the end of the century.
This damage will be compounded by ocean acidification, another impact of higher CO2 levels in the
atmosphere, as well as changes in the water’s oxygen content.