With his research on sharks, marine biologist James Lea (film Older Than Trees) has contributed to the establishment of marine protected areas. We asked him five questions about his work.
We tend to see different changes at different times scales, but generally it takes quite a few years for us to start seeing a good recovery. There is a very good example from a protected area in Mexico called Cabo Pulmo, which is well protected and has had great recovery, but it actually took more than a decade for the sharks in particular to really start and recover properly. This is because they have such slow reproduction compared to so many other fish – they take many years to mature, and then only have few young every year or two. But once and area does start to recover, the whole biomass in general really starts to increase and start to return to a proper healthy ecosystem.
Should people visit marine protected areas? How much tourism can an area tolerate?
think it very much depends on the location and how it’s managed as to what can be considered a sustainable level of tourism. For many species tourism has great potential to offer alternative livelihoods for people while also funding the management of MPAs, and there are some countries that have created shark sanctuaries based on the value of shark tourism to the economy. So it has tremendous conservation potential, and people should certainly favour ecotourism operations that support protected areas. But also look out for signs about how well they are managed – for example check for codes of conduct about how to interact with animals, are there limits on numbers of boats or people in the water, and is it clear how funds can feed back into local conservation initiatives and capacity building.
The single biggest challenge is how to combat overfishing – the greatest threat to sharks is quite simply that we are exploiting them much faster than they can reproduce. So yes, getting the data to show what needs to be done is a difficult, but the real challenging is changing peoples hearts and minds so that they actually want to make the changes that need to be made. So it’s definitely the most difficult step to convert science into real, meaningful change. But what gives me great hope is that there is a growing change of momentum in favour of shark conservation measures, which was recently exemplified by more than 140 species of shark now being listed on CITES, which restricts international trade and now covers more than 90% of the fin trade.
