Some fish just have an irresistible appeal to me. While I like the thrill of encountering an animal larger than me, the tiny critters are often just as interesting to observe. All those little folks that inhabit small portions of the reef have an important role in everyday reef ecology.
For me one of those favorite little folks is the redlip blenny. I dont know why, but I just love watching that little face dart about the reef, maintaining its feeding grounds and protecting its space. Maybe the attraction is the big eyebrows, called cirri, or the reddish lipstick tinge of the lips. Or the way they will look at me, run away (not the first time thats ever happened), retreat into their lair, and then peak out as if to say, ok, you startled me at first, but you can stay and play.. If you have the patience and bottom time to hang out for a few minutes, they will let you get pretty close.
Typically when I find one, I find several. They are territorial concerning other redlips, but not so much with other species. Check out this YouTube video of two redlips harassing each other over their boundary line: http://youtu.be/tpSVXfTmpTc
Naturally, I had to find out what all the fuss is about. Seems as though there are several scenarios at work among the redlip blenny population. Of course, the establishment of territories is fundamental to many species, but male redlip blennies have an ulterior motive.
More real estate means more nooks and crannies to build nests. They build up their coral and algae estate in an effort to attract females to pop in and make an egg deposit. Females shop around. In this case, bigger and older is better. Larger size and paternal experience are more attractive to the selective females.
Since the female has to leave her territory, traverse open space and make it back home, I dont blame her for making the most of the trip. Beyond the predatory danger they face, squatters are prevalent among the redlip population. Instead of snooze, you loose, here its love and loose [your space].
Male redlip blennies are good dads. They maintain the nests, and even secrete an antimicrobial mucus that helps keep the eggs healthy until they hatch. Redlip dads have anal glands that are part of the attraction for the females. See http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1686180/ for a good study of the antimicrobial properties. Near the bottom of the page, under Supplementary Material there is a little film clip of a male doing the rub-a-dub-dub on a nest.
In a similar study (http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2435.2009.01608.x/full) of anal gland secretions for peacock blennies in the Adriatic Sea, females sought out males with larger glands typically older larger males. According to the study, The finding that females prefer males exhibiting larger glands, capable of producing more secretion, provides the first indication of possible female choice for the direct benefit of male antibacterial protection.
Another study shows that males will also take over an abandoned nest, provide care and attract females to lay additional eggs. So, if the guy next door gets eaten, the neighbor is capable of snatching the new territory and keeping the nest clean and bacteria-free, enhancing the survival rate for that nest.
All of these paternal features seem to be worth the risk of finding the best mate. In Barbados, redlip females were studied to assess the energy expense, risk of predation, potential loss of territory and harassment by other fish in their search for the perfect male. What an adventure! Sounds like there should be a book and movie rights based on that true life story.
Females increased their travel time and distance, fended off territorial defenses as they zipped through another blennys or a damselfishs no-swim zone, and sought the large, older males for mating. The benefits of choosing the larger, more productive and caring males outweighed the effort of running the gauntlet.
Females bypassed younger, smaller males on the way to big daddy. In some observations, when the female arrived, there was a line. Oh well, the good ones always seem to be taken!
I want to spend more time watching redlip blennies. They mate beginning at first light in two week cycles that start 10 days before the full moon. The mating sessions last about three hours each morning, and males generally have female visitors every day. Sometimes the same females come back, but usually there are different mixes among males and females. Females spawn every other day with up to five different males during the two week session.
Next time you are on the reef on a morning dive and see a redlip blenny scooting around, it might be worth the time to hang out and see what happens.
Quick reminder: this evening, Friday, Feb. 1, from 5 to 7 p.m., the Coral Restoration Foundation (www.coralrestoration.org) is hosting a Grand Opening celebration of their Education Center at 5 Seagate Blvd in the Pilot House Marina. This would be a great time for you to come out and see what coral restoration is all about. Hope to see you there!
Tim Grollimund is a freelance photographer and PADI divemaster based in Key Largo. He can be reached at firstname.lastname@example.org or through his web site at www.timgimages.com. Tim is actively involved with the Coral Restoration Foundation and the Aquarius Foundation.