This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American
We arrived at Salomons Atoll while it was still dark and waited for first light to enter the lagoon. The captain of the Pacific Marlin, Neil Sandes, has obviously done this many times and the GPS waypoints are well known, but it is still a good precaution to be able to see where you are going.
We started work immediately -- Pete Carr visited the islands to do vegetation mapping and bird counts while the rest of us went diving. The morning’s dive was on the reef slopes on the east of the atoll, off Ile Jacobin. The water was very clear but a strong current was running which made the work much harder. Running a 50 metre tape transect in a strong current is no easy matter.
Bob, our expedition doctor, has been assigned to work with Nick, our ichthyologist (“fish guy”), on fish counts and an interesting project looking at parrotfish behavior. In areas where there are a lot of people, parrotfish will swim away from a diver while the diver is still fairly far away. The extent of their wariness has been shown to relate to catchability – i.e., their vulnerability to fishing. Nick was interested to see how parrotfish, which have never seen a diver, will react. Bob has to swim towards the parrotfish and as soon as the fish starts to flee, he drops a marker and swims to where the fish was when it swam away, then measure back to the marker using a tape measure. It is very clear from the start that fish here are much less nervous of approaching divers than has been recorded anywhere else in the world. A reference on this is given at the end of this post.
On supporting science journalism
If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.
On the way to our afternoon dive site, we encountered an abandoned longline. We radioed in to the Pacific Marlin, which came and removed it. There are always going to be poaching attempts on a marine reserve, but the Pacific Marlin is constantly patrolling.
After the afternoon dive, the water over the reef flat was too shallow to drive the boats over so we walked them over into deeper water. The trick here is to avoid treading on the Diadema urchins while man-handling the boats.
All work was completed at the end of the day and we thankfully had a cold beer on the bridge watching yet another spectacular sunset.
Reference: Januchowski-Hartley FA, et al. (2011) Fear of fishers: Human predation explains behavioural changes in coral reef fishes. PLoS ONE 6: e22761.
Previously in this series:
Conserving Chagos: Science Expedition to World’s Largest “Ocean Park”