Shallow water tigers and deep water reefs….

Things have been a bit quiet over here on the fieldwork front.  We were not sampling for September so a great deal of time was spent maintaining gear and playing with the data from the first quarter.  We got some pretty distinct spatial trends that were echoed by between the two survey techniques.

The winter sampling period officially kicked of on the 1st of October with torrential tropical downpours – so much rain that the storage cisterns in the laboratories overflowed!  Baited video sampling has begun and has already seen a number of sharks, including the usual Caribbean reef and nurse sharks but also a young female tiger shark, only the second we have seen on the baited video surveys.  A couple of the sharks we have seen have had a sense of humor and have torn off three bait bags and one complete bait arm – considering we did not loose one bait bag in the whole of the first quarter this is a pretty impressive statistic.  It makes for some good video footage but causes problems for us as it means we have to redo the set again.  Hopefully this is a game they will get tired of soon!

We downloaded our VR2 array last week and pooled all the data for our fourteen acoustically tagged sharks.  Nearly all our tagged sharks have given us data indicating a good recovery from the surgery necessary to implant the tag.  The surprise in the data was from the three tiger sharks.  Two of the three sharks have been within our array for over a month with brief disappearances of a few days on occasions.  Both sharks have been using heard at the 30m drop off of the Exuma sound and also within our inshore array in water less than 2m deep only and less than 200m from the shore.  The eleven Caribbean reef sharks with transmitters are continuing to display high levels of site fidelity and interestingly one of the depth transmitting tags has been recording depths of 100m (330ft) which supports the regular deep diving behavior observed in this species in Belize.