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links to:

Journal of the OSF
Volumes 1-10, click for pdfs
Recommended Fish Links

Fish glossary and dictionary

The Australian Museum- larval fish
Smithsonian Tropical Res. Institute
Southeast Fisheries Science Center
Smithsonian NMFS- fish larvae
Love Lab- UCSB (must-see fish site)
The Barcode of Life DNA database
and completely unrelated...

My project page is being updated, the following is from the past few years:

I have worked on a wide variety of topics in reef fish biology. My dissertation was on the population biology of a coral reef wrasse, but I have since concentrated on larval fishes and collected and catalogued tens of thousands of fish larvae in the open ocean as well as on the reef. In addition, I discovered two new species of razorfishes in the Galapagos Islands and studied behavioral ecology and mating systems in the Caribbean.

My recent projects primarily focus on exploring the role larval ecology plays on the population biology, genetics, and biogeography of coral reef fishes. Virtually all coral reef fishes have a larval stage that lives in the open ocean for weeks or months before settling onto a reef. Since so much of the life of coral reef fish larvae is completely unknown, it is an interesting and challenging pursuit. I particularly like the detective work and deduction required to infer what is happening in the plankton from the few glimpses we have into the hidden life of fish larvae. Essentially all I have to work with is my collections of larvae from the plankton and, fortunately, a very serendipitous phenomenon- the formation of daily rings on the otoliths of these fishes. Otoliths are calcium carbonate accretions (stones) in the ears of fishes used for balance and hearing. The otolith of bony fishes grows by adding increments to the surface each day, like an onion, leaving alternating dark and light lines which closely resemble tree rings. Often these increments are laid down each day and transitions can be detected which correspond to hatching, settlement, and other life history events. These daily increments are incredibly valuable as a record of age, previous growth, and even the chemistry of the environment to which the larva had been exposed. I helped pioneer this powerful new aging technique in the 1970s and 1980s, and have been using otoliths since then to explore all kinds of questions about the life of reef fish larvae. I trained at the University of California at Santa Barbara, known to be a hotbed of rigorous hypothesis testing. However, larval fishes living out in the open waters are not the most conducive subjects for this form of research. The Santa Barbara philosophy is very well-suited to barnacles and algae and other more "tangible" organisms and systems and I wholeheartedly endorse it. Yet, my research is more exploratory and "phenomenological". While this approach is less "exact" than the usual rigorous methodological approach to scientific questions, i.e. erect an hypothesis and go out and measure the quantities required to accept or reject the hypothesis, it is more intriguing. I do admire and promote rigorous approaches, yet these just aren't that easy for this line of research. There are a number of biologists who are hewing to the line and testing hypotheses on the life of larval reef fishes (at AIMS and the Australian Museum) and I highly recommend their work. However, I prefer to ask more general questions and deduce what may be going on by assembling pieces of a puzzle. I particularly like the idea that each fact discovered narrows down the world of possible phenomena and can be used to reject a proposed model and encourage an alternative. While it doesn't build a correct model, it is, in essence, a process of elimination spiralling around the true model, and, in my opinion, a lot more fun and adventure- rather like a detective instead of a watchmaker....

I have a variety of projects currently, often slowly, underway in My first project in this area is on the pelagic larval duration (PLD) of the rainbow wrasse, Thalassoma lucasanum. I have been studying the early life history of this very common fish for many years with Jerry Wellington (formerly at the University of Houston). We discovered that there is a large seasonal difference in the PLD of this fish and some others in Baja. This is particularly unusual, since reef fish larvae generally have little temporal variation in PLD, at least much less than the huge differences we found, which ranged from 40 to 120 days from one season to another. Given that so little is known about where fish larvae go and what they do there, this anomaly may provide some very useful hints. Finding this focus of extreme variation allows a set of interesting questions to be asked: what causes the difference? are the larvae coming from different places? do they grow at different rates or just stay longer and grow larger in the plankton in different seasons? is this pattern uniform or variable along the coast of Baja California? does the variation track changes in water temperature or current regimes? Is the microchemistry different? We also found that El Nino exaggerated the pattern: during the El Nino PLDs were very short, and during La Nina PLDs were exceptionally long. Clearly this site and this species are an excellent case study of sources of variation in larval duration. A second study in Baja concerned the effects of very short and very long larval lives on population genetics and biogeography. This research was in collaboration with Cynthia Riginos (U. Queensland) and building on the work of Mike Brogan in Baja. We studied the small blennies in the Sea of Cortez because this group of fishes, unlike most others, displays a very wide variety of larval strategies- from extremely short larval durations and a strictly inshore distribution of larvae in the triplefins (such as Axoclinus nigrocaudus) to long larval durations and offshore larval distributions in the Panamic fanged blenny, Ophioblennius steindachneri. Our findings (see publications) show an impressive difference in genetic heterogeneity (genetic population "structure") between the two species: triplefins are clearly genetically different between sites, even within the Sea of Cortez, indicating essentially closed populations with larvae remaining in the local area, while the blenny has no apparent genetic differences between populations we sampled. This is one of the first clear documentations of the effect of larval ecology on genetic population structure in reef fishes. Other projects I am doing in Baja include general collections and identifications of reef fish larvae and collaborations on the population ecology of the snappers in the region Galapagos Islands

The Galapagos Islands are a very interesting place to work, although the fishes are not nearly as exotic as the more famous tortoises, iguanas, penguins and finches of these islands. There are many endemic fish species as well as a combination of warm-water tropical fauna and cold-water Peruvian province species in the southern and western islands. In addition, the Galapagos Islands are at the epicenter of the El-Nino Southern Oscillation (ENSO) event that affects world-wide weather systems and has important effects on marine life in the tropics, especially in the eastern Pacific region. Recently, we assembled the observations of reef fish biologists in the region, including Jerry Wellington (ex-University of Houston), Ross Robertson (Smithsonian Tropical Research Institute in Panama) and Benjamin Ruttenberg (University of California, Santa Barbara) to assess the impact of the massive 1997-1998 ENSO on reef fishes, especially the wrasse family that I have been surveying for many years. We found that the labrid reef fishes appeared to do well during the ENSO, with heavy recruitment noted for most species. The most notable finding was the arrival of a species previously rare in the Galapagos, Stethojulis bandanensis. I found numerous newly-recruited juveniles in many places in the islands at the end of the ENSO in 1998. Interestingly, they had a relatively short pelagic larval duration, only about 30 days, so if they had originated elsewhere they had traveled very fast. Since it is very unlikely they originated from the Galapagos, the nearest source population would be Cocos Island, many hundreds of miles away. In other words, there must have been some rapid long-distance dispersal for these larvae- a phenomenon not easily documented for reef fishes..

My first research project in the islands was a survey of the pelagic larval duration of the labrids (wrasse family). During the visit I discovered a new species of razorfish unknown to science. Razorfishes are a sub-group of wrasses that live on sandbeds and dive into the sand when disturbed. As a result, their bodies are very narrow and their head ends in a sharp keel (the "razor") allowing them to swim through the sand. This new species had eluded the previous zoologists that had collected fishes in the islands, starting with Charles Darwin (in the age before masks and snorkels, fishing was the only way to collect fish) up to the present. The reason was probably that razorfishes live on open expanses of sand and most biologists naturally gravitate to the more interesting reefs. Also, this species congregates in large colonies in particular places- making it a matter of luck whether one explores that particular area. Fortunately, I stumbled into a large colony of these fishes on a dive on the island of Marchena and, realizing these were an unknown species, collected many of them with a small spear. Needless to say, it was one of the more exciting days of my life. The fish, since named Xyrichtys victori, is a spectacularly colored fish: the females are bright orange and the males are iridescent blue-green with prominent black blotches that vary from individual to individual. Variation in markings to this degree from one fish to the next is very rare among reef fishes, and perhaps evolved in this species to permit individual recognition of displaying males, since it occurs only in the male of the species. Since then I have collected two forms of juvenile razorfishes, one of which is morphologically unusual, and must represent a new species. I plan to run some DNA sequence analyses to see where that razorfish places among the known species in the region.

History: I did most of my early research in the Caribbean during the 1980s. My dissertation was on the population biology of reef fishes, in particular, the bluehead wrasse, Thalassoma bifasciatum. In those days there was little interest in younger fishes, which were considered mostly food for the older ones. The traditional view of ecosystems was concerned with carrying capacities and the factors controlling the numbers of adults observed (and ecology was a relatively new science, which only really got going in the sixties). Typically, from experience with terrestrial biology, the important factors were predation and competition- with a bit of physical factors thrown in. The advent of scuba and a developing interest in the tropics encouraged the new wave of young academic ecologists to start to look at coral reefs in a similar manner, and, very quickly, they began to find that reefs were not so simple. Interest in the role of larval settlement was first sparked by Peter Sale among the (few) tropical marine fish biologists at the time. Indeed, in May 1976, there was a mini-symposium at Cornell University on the role of recruitment in the ecology of reef fishes, where Peter Sale started some arguments that still continue today. By pure coincidence, I was a sophomore taking the ichthyology class next door, blissfully unaware of the existence of any controversies on palm-studded islands far away (I was pushing sheets of ice out of the way in pursuit of freshwater stream fishes at that time). My research project after ichthyology class was to use otoliths to age some fishes in the streams around Ithaca, New York. Ed Brothers, who was working on otoliths after studying the life history of gobies at Scripps in San Diego, had just started as a professor at Cornell, and he taught me how to look at daily otolith increments. After doing a project on the age and growth of a freshwater cyprinid fish, I was ready for some warmer weather and applied to Hawaii, Florida, and Santa Barbara for graduate school. I went to UC Santa Barbara where Bob Warner was studying the behavioral ecology of the bluehead wrasse, and then spent some years at Bob's research site in the San Blas Islands of Panama. Daily otolith increments happened to be ideal for studying the early life history of reef fishes, and I started to collect data on the settlement patterns and the age and growth of larval and juvenile bluehead wrasse. After many years I have returned to my larval collections I made for several years in the mid-1980s in the San Blas Islands of Panama. Unfortunately, I had spent hundreds of hours making ink drawings of the larvae, and now the web and digital photography have essentially rendered drawings old-fashioned, and I have now begun to photograph all of my larvae. As one can imagine, this is a gigantic job, since there are perhaps a thousand species of reef or reef-associated fishes in the Caribbean. I started with the gobies, since they account for well over a hundred of these species and I like a challenge. Thus far, I have identified and photographed almost all of the shallow-water gobioid genera, and I am beginning to photograph other families of fishes. After that I can move on to my eastern Pacific collections and even the large collection of larvae I have from Rangiroa, in French Polynesia. But, the Indo-Pacific is daunting- since the number of species goes up exponentially, and I depend on the process of elimination, to a large degree. By the time I get to those larvae, molecular techniques, such as dna fingerprinting or barcoding, will likely be the method of choice for identifying larvae to species.

Benjamin Victor, e-mail: ben at-sign, then

Reef Fish Larval Guide
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