After 8 weeks, 143 dives and 52 hours of behavioural observations I am leaving Wakatobi. During this time I have been lucky enough to witness pygmies conducting daily courtship rituals, mating, giving birth and even fighting. I have collected some great data and will have plenty to work on when I get home.
This week has been a brilliant finale. My new group of six pygmies on the House Reef, which I have studied for just under three weeks, have yielded some interesting finds. The three males all gave birth at some point over the past week. Since I have been observing them for such a short time I was unable to know exactly the stage of the male’s pregnancy and therefore was uncertain when they would give birth. Luckily, now I have become something of a pygmy seahorse whisperer and was able to make an educated guess as to the day the males would give birth.
One evening the behaviour between one of the males and his mate was slightly different to usual. Ordinarily, only the male gets really into the pair’s courtship ritual but I noticed the female too was pretty excitable. This indicated to me the female had prepared some eggs, which she must begin to do several days before transferring them to the male. The purpose of the courtship ritual is to synchronise the pair’s reproductive systems. It is much better if they know the state of their partner’s cycle as this reduces the time wasted between broods. So, the female’s excitement indicated she was ready mate. From experience I knew when this was likely to be so got up bright and early the next day to try and witness the event.
We set off with time to spare but had a current against us to reach the gorgonian seafan where the group lived. Unfortunately this put us behind schedule and we missed the birth! Just as we arrived the male released the last of his brood and was flushing out his brood pouch with seawater. The male then swam about for the next twenty minutes, seemingly searching for his mate. They sleep together every night in the same protected area of the gorgonian and this is where the majority of social and reproductive behaviours are carried out. The female had left this area but after twenty minutes or so returned and the pair began courting.
The male was still visibly wrinkled with stretch marks but began courting his mate with fervour. Several times he inflated his brood pouch with seawater and flushed it out again. After quarter of an hour of these behaviours the pair rose up together from the gorgonian and intertwined their tails. They floated free from the gorgonian and held together their urino-genital openings (the technical term for the private bits of pygmies). This union lasted thirty seconds, during which time the belly of the female went from enlarged to wrinkled. The male conversely took on the eggs and swelled as they filled his brood pouch. I had witnessed pygmies mating once before but they kept the act to the seclusion of their protected sleeping area. The pair this week were real exhibitionists and put on an x-rated show for us! An amazing end to an eventful eight weeks of pygmy seahorse research!
Finally, but most importantly, as I wrap up my last blog I would like to thank Wakatobi Dive Resort for their invaluable support and enthusiasm in my project. Without their involvement this study could never have got off the ground. I have made many friends over the six months I’ve spent at the resort over the past two years but I look forward to visiting them and diving the amazing reefs again one day. Thanks also to everyone who has read and commented on my blog over the last eight weeks. Keep checking back I’ll be writing more blogs in the future! Now I will be working on writing up my studies. So hitting the books, but maybe fitting in a few dives too!
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