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Life isn’t always better under the sea.
A combination of overfishing and environmental changes have cut the population of the worlds oceans nearly in half, according to a new report from the World Wildlife Fund.
The report, which looked at 1,234 species of mammal, bird, reptile, and fish, found that between 1970 and 2012, populations declined by 49 percent, with some species hit much harder than others. Commercially valuable species like tuna and mackerel declined by 74 percent, and sea cucumbers (seen as a delicacy in some parts of the world) saw their populations reduced by over 90 percent in specific areas like the Galapagos and the Red Sea. Currently, harvesting sea cucumbers is banned in the Galapagos, though illegal fishing still occurs.
The report also found that marine habitats were in decline, with 1/3 of all seagrasses lost, and coral reefs facing extinction as early as 2050.
The report also says that there is some hope, if policy makers prioritize the protection of the ocean and climate at events like this fall’s UN climate summit in Paris.
Fortunately for the oceans, there does seem to be a sea change in conservation policy with increasing protection of certain marine areas in the United States and around the world. In recent years researchers have identified the conditions that allow marine wildlife reserves to succeed and flourish. They have to be large, isolated, established places with strict enforcement of fishing and development bans. If conservation plans (including sustainable fishing practices and action on climate change) work, some populations could start recovering.
And, now we know, there’s plenty of room for more fish in the sea.