So you might wonder why after not updating this site for so long I’m putting up a post about Devils Hole pupfish. Well, they are what have been consuming most of my time. Besides managing SeaCortez, I’m also a researcher with the USGS Arizona Cooperative Fish and Wildlife Research Unit where I specialize in the captive propagation of endangered fish species, and on the functional genomics of Devils Hole pupfish (Cyprinodon diabolis). So, instead of more info about breeding marine species, this time I thought I’d share a bit of info about one of my other passions – the Devils Hole pupfish, and some really cool footage we captured of a mini tsunami in their habitat in Death Valley following a recent earthquake in Baja, Mexico.
So, a bit of background about the pupfish: They are probably the most endangered fish in North America, possibly the world. Small and silvery blue, Devils Hole pupfish are really an attractive fish that has the smallest geographic distribution of any vertebrate species. Cyprinodon diabolis is found in a 6 foot wide opening in the top of a deep cavern (scuba divers have been down to 440 feet and haven’t seen bottom) that extends into a carbonate aquifer. The fish live near the limits of their physiological limits. The water is a near constant 93 degrees Fahrenheit, and often has dissolved oxygen levels of only 2ppm.
Although only about 500 individuals were counted at maximum population levels, the population reached a critical low in 2006 when only 38 fish were counted. The population has rebounded to about 150 fish, but they are still critically endangered. No captive populations of the pupfish exist outside of Devils Hole.
While the footage looks like it would be pretty traumatic for the pupfish, it can be beneficial as well. These occurrences do a nice job sweeping fine silt off of the spawning shelf.
From the USGS press release on the event:
For tiny Devils Hole pupfish, startling video shows it must have felt like a “huge tsunami” when violent water-level oscillations from an earthquake 300 miles away disturbed the small ledge they live on in a single Mojave Desert cavern pool for some 15 minutes.
To see video clips, visit http://gallery.usgs.gov/videos/229
These water-level oscillations in the cavern in Death Valley National Park were caused by the magnitude 7.2 El Mayor – Cucapah earthquake and an immediate aftershock that occurred on April 4.
The video from four U.S. Geological Survey cameras shows significant water-level oscillations, causing great disturbance to the shallow feeding and spawning shelf critical for the continued existence of these fish, said Ambre Chaudoin, a graduate student in fisheries with the USGS Arizona Cooperative Fish and Wildlife Research Unit at the University of Arizona, Tucson.
“The shelf substrate sediment was largely redistributed as a result of the water oscillations,” said Chaudoin. “Such disturbance can be important because the spawning shelf is less than 13 feet long and 7 feet wide, smaller than many walk-in closets.”
Federal and state surveys done within a week after the April 4 earthquakes revealed about 118 individual fish in the pool, an increase from about 70 the year before. Also, biologists saw newly hatched larval fish and evidence that the fish were spawning.
The violent oscillations, though, washed away algae that are essential to the food web of the critically endangered fish, though biologists hope they will grow back quickly. Biologists with the National Park Service, U.S. Fish and Wildlife Service and the Nevada Department of Wildlife will carefully monitor Devils Hole for any harmful after-effects to the fish.
Ambre and fellow USGS researcher Olin Feuerbacher happened to be conducting Devils Hole pupfish behavior surveys on April 4, the day the earthquake struck. They caught the earthquake-induced wave action on video cameras they had just reconnected to their recording position inside the pool 10 minutes before the quake struck.
“The fish begin to move out of the camera’s view as the waves start getting bigger, and then, because of all the sediment being stirred up, you can’t see the fish. As the waves grew stronger, the fish likely moved into deeper waters,” she said.
Paul Barrett, a FWS biologist who leads the Devils Hole Pupfish Recovery Team, said that water-quantity and -quality changes after an earthquake can affect sensitive aquatic environments by changing water levels or by reducing the amount of algae or invertebrates that live on the ledge. But sometimes they can be beneficial as well.
“Earthquakes, such as a 1978 temblor in Mexico, can set up waves that clear the spawning shelf of the algae upon which the pupfish rely, however depending upon the time of year, the algae may regenerate quite rapidly,” said Barrett. “Furthermore, quakes can serve a useful purpose in shaking silt and other fine particles that have washed into Devils Hole off of the spawning shelf and into the deeper waters. This frees important space between the substrate particles where the Devils Hole pupfish larvae seek refuge.”
In fact, said Barrett, after the April 4 Mexicali quake, the National Park Service recorded a slight increase in larval abundance as compared to a similar survey a few weeks before the earthquake occurred.
The phenomenon of earthquakes and corresponding seismic effects on water wells, streams, springs, seeps and lakes is well known. Generally, large earthquakes (greater than magnitude 6.0) with epicenters hundreds to thousands of miles away can cause hydrologic responses in water wells and surface-water bodies. Hydrological effects from the April 4 earthquake were also noticed in places as far away as Virginia.
Devils Hole pupfish populations remained about 400-500 individuals until the late 1960s when the water level in the pool dropped in response to pumping of nearby irrigation wells. Pupfish numbers declined precipitously, and though water in Devils Hole is now maintained at a minimum level, the pupfish are still greatly imperiled. With intensive management efforts, pupfish numbers are increasing from a critical low of just 38 individuals in 2006 to about 118 in the 2010 spring survey after the recent temblor.
Although Chaudoin and USGS researcher Olin Feuerbacher said they would have liked to have seen first-hand the effects of the quake on the hole, they were fortunate in having removed the tiny viewing platform they had been sitting on right above the pool before the quake hit. “Our viewing platform is about 50 feet below ground level, only a few inches above the water surface of the pool,” said Chaudoin. The earthquake caused water to hit our cameras about 4 feet above the platform, so it probably would have been a rather unpleasant experience if we had been on the platform,” she said.
The USGS scientists are using video to help them assess relationships between environmental conditions and spawning in the pupfish to help managers better understand the habitat and spawning requirements and ultimately help in captive propagation. This study is being conducted by the USGS Arizona Fish and Wildlife Cooperative Research Unit and is funded by the U.S. Fish and Wildlife Service, in partnership with the National Park Service and Nevada Department of Wildlife.
About Devils Hole Pupfish
Contained deep within a limestone cavern in the Mojave Desert, Devils Hole is a constant temperature, 10 by 50 foot pool of water that provides a window into the extensive carbonate aquifer within the Amargosa Valley groundwater basin. Devils Hole pupfish live only in Devils Hole, dependent on a tiny spawning shelf less than 13 feet long and 7 feet wide. There, these colorful fish – the males a sparkling blue, the females a more subdued grey-blue or silvery-blue – have made their home for thousands of years near the upper limit of its temperature tolerance – the water remains around 93 degrees — and near the lower limit of its oxygen tolerance. Adult fish average only about one inch in length and are unique among pupfish in lacking pelvic fins.
Each spring, just enough sunlight penetrates Devils Hole to allow food in the form of algae and small invertebrates to grow in the spring. This food supports a new generation of pupfish before the previous year’s fish die of old age. No one knows how deep the pool is, but the pupfish live in the upper 80 feet of the pool.
You can find the press release here
Tags: Baja, Earthquake
Yes, the last post before we jump into the meat of this little endeavor. Lets skip ahead fifteen years so I can explain where I am now, and put a little perspective on just why the heck I’ve decides to write all this.
In the end, melding science and photography with a little splash of English-minor turned out to be a pretty good combo. Since my graduation, I’ve worked in molecular epidemiology, cancer biology, microbial pathogenesis, high throughput genomics and aquaculture diagnostics. Heck, I’ve even taught high school, become a scuba instructor, and started a fish farm. I’ve also completed a Master’s in Applied Biosciences, and recently completed a Graduate program in Entrepreneurship at the McGuire school. As an offshoot of the entrepreneurship program I’ve now launched a molecular diagnostics company. Yes, I’m flakey and easily bored so when I start to get good at something, I typically become uninterested, quit, and move on.
The path after graduation has taken many twists. Throughout, a continuous source of interest and inspiration has been with the ocean and the Sea of Cortez. Every time I am able to slip under the surface of the Sea of Cortez, it feels like a homecoming or visiting an old friend. The underwater topography and species mix is unlike any other in the world. There is a certain soothing feeling that comes from knowing a region so well, mixed with an excited anticipation, from the fact that what I do know is dwarfed by what I do not. This region is still largely unexplored and many species exist only within the relatively small confines of this sea.
So now, to some extent I have come full circle. The Sea of Cortez and those that have studied and protected her have given me so much, now I feel I can give something to those that are embarking on their own exploration of this region. It started with a couple of (still largely unfinished and sometimes cheesy) websites with some travel info about Baja and San Carlos, but my major undertaking is the SeaCortez site. At SeaCortez, I’m hoping to promote an understanding of the unique natural history and ecology of the Sea of Cortez, as well as to promote responsible utilization of the region. I truly feel that the more people can come to understand something as special and fragile as the Sea of Cortez the more likely they will be to protect this desert sea. A part of this project will be looking back at the changes that have occurred in the Sea of Cortez, and at the changes in myself and those around me that have been inspired by the Sea. I hope that by examining some highlights of my earlier field notebooks I can share with others the wonder and sense of discovery that can be found in these waters and to inform and inspire others to make their own treks into the vermilion sea.
As discussed in part one of this intro, some of the pre-trip planning I am undertaking for another possible expedition down Baja includes going back through my field journals from earlier trips, particularly from the summer of 1992, my first foray into the Baja Peninsula. Of all my travels in Mexico, this was by far the most inspirational and educational trip to date. True, this was in part due to the fact that I was a wide-eyed and idealistic college student relatively new to marine biology, but it was also due in large part to the caliber of people on the trip.
At the time of my first trek into Baja, I was a marginally dissatisfied fine-arts major at the University of Arizona that had found my childhood interests in science rekindled after taking up scuba diving. As an aspiring wildlife and underwater photographer, I was repeatedly told both by my compatriots and professors in the fine arts department “You have talent – why do you want to waste it taking pictures of fish”? Any type of outdoor or nature photography was generally met with scorn by others in my department.
Just imagine my joy at finding out that while my scientific leanings weren’t terribly popular in the photography department, my photography was extremely well respected and valued in the science department! Not only that, but there was an upcoming marine biology field course that was headed down Baja for 5 weeks, led by some of the most well known biologists working in the Sea of Cortez. Among them was Dr. Donald A Thomson, one of the three authors of Reef Fishes of the Sea of Cortez, the bible for ichthyologists working in the Gulf of California. He had led this field each summer for 23 years by the 1992 trip. Another individual leading the trip was Alex Kerstitch, an internationally known underwater photographer and another author of Reef Fishes of the Sea of Cortez. Both of these individuals would become close personal friends and mentors and have been tremendous sources of inspiration for which I will forever be in their debt. Needless to say, it was due in no small part to these two individuals that a semester before graduating with my fine arts degree, I ended up changing my Major to a double in Ecology and Evolutionary Biology and Molecular and Cellular Biology. My gen-ed advisor actually giggled as he crossed off all of my once-valuable requirements and moved them to the elective pile. Yep, 7 years to get the two Bachelor’s degrees… But I did at least get to claim a minor in photography.
This summer marked the fifteen year anniversary of my first crossing into Mexico’s Baja peninsula, the small sliver of land that separates the Sea of Cortez from the Pacific Ocean. I had been to the Sea of Cortez before, but never Baja. I have returned to Baja many times since, but never has the experience been such an expedition of wonder, exploration, and camaraderie as I experienced in the summer of 1992.
As I prepare for another trip to Baja, I am studying my field journals from that 5-week expedition. Much has changed both in the Sea of Cortez, and much has changed with me. But more has stayed the same, for better or worse. As I begin this blog, it seems appropriate to discuss the “then and now’s” of the experience to put some perspective on what was learned and what one might hope for the future.
As it turns out, the trip to Baja was a rather formative experience. In the Summer of ’92 I had completed my sophomore year as a fine arts major at the University of Arizona. I had taken up scuba diving my freshman year and this had rapidly become an addiction. Soon I was rabid about underwater photography and even took an introductory class in marine biology so I could learn the names of some of the fish I was seeing. I had no idea that taking up this sport and enrolling in a 100-level elective would have such a profound effect on the direction my life would take.
I met an entirely new group of people in the Ecology and Evolutionary Biology department. Unlike many the fine arts people I knew, these nutty ecology types were generally friendly, easy going and loved to travel. Sure they were idealistic and mad about things, but these things seemed tangible and meaningful compared to the generalized discontent I had found in the arts college. In short, I found my social unit. Plus, Birkenstocks are much more comfortable than uber-cool combat boots, and you really can only wear black in Tucson for so long before you burst into flames.
Tags: Baja 92'
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