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clownfish_dives.md

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GPS coordinates are determined prior to departing by looking at a map of the dive site and selecting an anemone of interest to begin the dive. This could be the northern/southern most anemone at a site or the anemone where you left off at the last dive.

Once the boat gets about 250m away from the GPS coordinate, tell the boat driver to slow down by making a pinching signal with your hand.

Once the boat is 50m away, make the pinching motion again, at this point of the boatmen should be at the front ready to drop the anchor.

At 20m, signal to the front boatman to drop the anchor. Using this method, you can follow the anchor line down (the boat will have drifted off the GPS point), but the anchor will be very close to the anemone of interest.

A dive is usually swum with the current and the boat picks up the divers at the end. The search pattern depends on the shape of the dive site, but most are swum in a zig zag pattern, covering the bredth of the reef while moving from north to south (or vice versa depending on current).

In 2016, the fish catcher was the first person off the boat, searching for fish before they could be scared off by divers.

The fish catcher used a barrier net and a hand net to capture fish, and many times caught multiple fish at a time.

The fish catcher passed the captured fish in a hand net off to the field assistant who was also carrying a hand net. The fish catcher pointed out which anemone the fish came from and then continued to search for fish. In the future, leaving the fish in collecting containers instead of in the hand nets will improve conditions for the fish and prevent mortality. These collecting containers could be at the home anemone. We might need many collecting containers in areas that are heavily populated.

The field assistant would hold the fish while the data collector would hold calipers up to the fish and photograph the fish in the calipers so that photos can be assingend to fish number later based on time, size, and tail color.

The data collector records anemone number, size & tail color on data sheet (and time to the nearest second when near the home anemone)

The data collector scans fish to see if it is tagged. If tagged, the data collector records tag number on data sheet and the field assitant releases fish. If not tagged, the data collector takes fin clip, inserts pit tag, and records fin clip number and pit tag number on data sheet. After these have been recorded, the field assistant can release fish.

If anemone is not tagged, the field assistant hammers tag into substrate near the anemone where the fish was caught. A zip tie is included in the hole of the tag to stick up as a flag once the tag has been covered with algae.

In the future, having a separate anemone data recorder and fish data recorder would improve data quality. Currently, the fish data recorder is so busy scanning fish and collecting tissue that there is not time to look up and see where the fish are coming from and if smaller fish are on the anemone that are too small to be caputred.