Hi,

Marine Protected areas can have various degrees of protection from pure No-take areas to allowing certain types of fishing. I would suggest looking into periodic closures. However, no take reserves have been known to  sometimes take decades before detecting benefits to fisheries (such as spill over).

This article might interest you as it looks at long term benefits (and so might indirectly) help you determine the consequences of re-opening marine reserves.

https://www.researchgate.net/publication/51073903_Enhanced_biodiversity_beyond_marine_reserve_boundaries_the_cup_spillith_over

Article Enhanced biodiversity beyond marine reserve boundaries: The ...

Hi Natalie and thanks for reply

Yes, it is a lot of studies of the effects of marine reserves. We are working closely with municipalities here in Norway to implement coastal marine reserves. However, the politicians (for obvious resons) want to have a time limit for how long the reserves should last. It would therefore be of interest if it was a good study out there documenting the effects of opening up a reserve.

Hi Alf,

I have been looking for the same kind of study myself, and after exhaustive searches have concluded that there are none! Natalie's suggestion of looking at periodic closures is the closest thing you will find right now. Sorry for the negative answer.

Aleks

The most comprehensive study I know of, that attempted to answer the question  was the work by K. Sainsbury and others as part of a long term study on the effects of trawling on the benthos.  They sampled Low trawl sites that  had zero or very low trawling in the five-year period prior to the survey, and also  medium and high trawling sites that had been fished reasonably consistently throughout the five-year period and in an increasing fashion. See the FRDC site and search for "Sainsbury" and "trawling" on that site:

http://frdc.com.au/Search//results.aspx?k=ALL(Sainsbury)%20ANY(trawling)%20(FRDCType%3A%22FinalReport%22)

Thanks for the answers.

Identified a new research project. Just have to wait until someone opens up a reserve for fishing...

Alf Ring