Ain't No Such Thing as a Marginal Habitat

A recent news report in the journal Science highlights an often overlooked edict of Mother Nature: In the long run, there is no such thing as a marginal habitat.

The story of Alaska's long-debated Pebble Mine in Bristol Bay is a case in point. Scientists have traced the boom and bust cycles of salmon runs throughout the region as far back as 10,000 years and concluded that we just cannot know which streams will have the most salmon, and when.

Salmon thrive when conditions are favorable, and just like trendy nightclubs, the hot spots change with the years. (But in the case of salmon, the choice locale depends not on the presence of a famous salmon starlet but on things like ice cover, rainfall, El Niño and other decades-long weather patterns).

Therefore, for a mine with an estimated lifespan of 80 years, it's deceptive (and wrong) to claim that only "less productive" salmon habitats will be affected. But that's exactly what the project's backers have done.

It is not just big industry that employs this argument when it comes to managing the environment.  Government and conservation organizations are also at fault for focusing too much on the "most abundant" habitats to protect.

Here's why it matters: In the wild, one virus doesn't often kill off an entire species because, chances are, some individuals naturally resist the disease; diversity of habitats works in a similar way, helping insure favorable spots will exist to support populations as the environment shifts over time.  From salmon to cod to sea turtles, access to an array of habitats can make the difference between survival and collapse.

We need to employ a precautionary approach and stop assuming we know which habitats are expendable.  Especially with climate change threatening more extreme weather, disease, and invasive species outbreaks, sub-optimal or outlying habitats today may transform into the productive refuges species depend upon down the road. It is of course, impossible to protect everything, but it is time we started erring on the side of more protection, not less.

So to those who say Pebble Mine will only affect the less important salmon runs, I say (riffing off Monty Python): every stream is good, every stream is needed, in the neighborhood.

Click here and here to take action to help stop Pebble Mine and protect Bristol Bay's salmon.

Photo Credit: echoforsberg on Wikimedia