Whereas much of our attention has been drawn to the recent anomaly in the sea ice cover of October in the Arctic (see here, and note the flatness in October) there has been some good news from the other cold side of the world: Antarctica.

On its latest meeting the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) decided to implement the largest marine protected area in the world: the Ross Sea. A map by the courtesy of MPAtlas.org can be found here. The area is 1.55 million km2 or roughly  2.3 times the size of France.  Thus far this title was held by the Pacific Remote Islands National Marine Monument in the US with 1.51 million km2, that president Obama created in 2014 by expanding a previously created National Marine Monument by George W. Bush.

Does size matter? Ecology tells us that it does. If there is one fundamental law in ecology it is probably the species-area curve. This curve predicts the number of species one can expect to find in an area of given size. The curve has been established empirically on all scale levels (see e.g. Rosenzweig 1995), and although its theoretical foundations are debated its typical shape is this:


(Punt, 2016). There are certainly decreasing marginal returns to area, but the number of species protected increases with area.

Of course size is not the only consideration. One worry with marine protected areas (MPAs) is how far protection actually goes. It is certainly not unheard of that fishing  is still allowed in marine protected areas. That is partly the case with the Ross Sea, although the largest part is a no-take area, meaning that almost everything in terms of extraction including fishing is disallowed.

What does make this area special is that the MPA is on the High Seas, an area of the world oceans that has been designated common heritage of mankind, and hence accessible to all. That means that for an MPA to be designated there has to be a consensus. This in turn means that, unless bargaining can take place over other topics at the same time, the MPA size and protection level is decided by its strongest opponent (see e.g. my article on this topic). This certainly seems to apply to this MPA which has been held off at various times by Norway, Russia and China until it was severely reduced in size and duration, as described by Rodolfo Werner in MPAnews.

That nonetheless the largest MPA in the world was created in the High Seas in this pristine area that so urgently needs protection takes away at least some of my general cynicism that has recently dominated my world view.

Cover image credit (Adelie Penguins): Jason Auch https://www.flickr.com/photos/10004136@N05.