Saturday, March 26, 2011

Duke trip

I usually accompany a group of Christopher Newport University students from Dr. Mollick's class http://www.cnu.edu/bces/profiles/mollick.asp to the Duke Marine Lab http://www.nicholas.duke.edu/marinelab/ this to assist in I.D'ing fishes and to help run the wet lab. But this year two of my staff members who formerly were students on the trip are representing the aquarium department next weekend. The trip is always fun and a great opportunity to collect invertebrates and some fishes, though this time of the year is not always productive. We always get many species of inverts and they usually end up on exhibit. A giant red hermit crab (pictured above) I collected a few years ago is the informal aquarium dept. mascot. I will ask the Jessi and Heidi to post their photos when they return

Friday, March 25, 2011

Skates and rays at the VLM

I am in the process of redecorating the interior of the Ray/Skate exhibit and will soon be replacing the southern stingray (Dasyatis americana) http://www.flmnh.ufl.edu/fish/gallery/descript/southernstingray/southernstingray.html that has outgrown the exhibit. Its tankmate was moved into our largest Chesapeake Bay Aquarium several weeks ago and is thriving.

We will be replacing the ray with several little skates (Raja erinacea) http://www.marinebiodiversity.ca/skatesandrays/SKATES%20and%20RAYS%20(profiles)/little%20skate.htm and one larger individual we acquired from Woods Hole as a young of the year.

         One of the 4 little skates to go into the exhibit.

The large, male little skate is on currently on exhibit with our chain dogfish - pictured below - (Scyliorhinus retifer), but he also will join the other skates.


I am attempting to install a piling/pier type structure inside the exhibit, which is now undecorated, except for the substrate. The new exhibit should be more attractive, more natural, and more dynamic. We are also adding graphics that include several other ray/skate species that we commonly collect in the future.  

Tuesday, March 22, 2011

Common Carp

The common carp (Cyprinus carpio) is an extremely interesting fish. They certainly are undervalued in the U.S. as people generally find them unpalatable. But they can be excellent sport, are one of the more intelligent fish species (in my experience) and can become very tame. The domesticated and highly prized ornamental koi are elaborate versions of the common carp. Many excellent sites have info and pictures that explain all the official varieties; a more general but informative site which also has products and pond info is http://www.koiandponds.com/varieties.htm and for serious koi enthusiasts:
http://www.tategoi-koi.com/Koi_Varieties.php But common carp are also very beautiful. In the next few weeks, carp in the James River will begin to move into the shallows to spawn. I often collect fertilized eggs from the vegetation in these areas to raise, mostly for fun.


Both of these carp are from the James River system: the fish on the left displays an interesting scale pattern, and the fish on the right was one of several I raised at the VLM from eggs collected at a nearby spawning site.

Saturday, March 19, 2011

Native trout spawning

A juvenile rainbow trout in the Mountain Stream exhibit at the VLM:

Each spring and fall our rainbow, brook and brown trout spawn on exhibit. The males develop a hooked jaw, or kype, with which he fights or drives off rival males with; they also become extremely colorful at this time. The male fans out a nest called a redd, then if he's lucky a female will join him on the nest to mate. She deposits small (3-5mm) eggs and he fertilizes them with milt. Unfortunately, other trout feast on the eggs, devouring most of them before they can settle into the substrate to mature. Eventually the juvenile trout, or fry, will emerge from the eggs, use up their remaining yolk sac and become free-swimming fish. At this time they begin to eat small invertebrates, plankton, etc, but in our exhibit we start them on artificial feed as early as possible. As soon as they are large enough to not be eaten, we put them in the Mountain Stream exhibit http://www.thevlm.org/mountainstream.aspx which houses other juvenile trout with native darters, shiners, sculpin, and various others. After about 6 months they will return to the adult trout exhibit.

Wednesday, March 16, 2011

Loggerhead Sea Turtles

As part of a collaboration with North Carolina Aquariums, the VLM raises juvenile loggerhead sea turtles that have been collected as hatchlings, until the turtles are ready for release. Their state-wide conservation program (http://www.ncaquariums.com/conservationresearch/sea-turtle-conservation) helps many sea turtles yearly and is an excellent educational tool for the people of North Carolina and our visitors. Some of the released turtles are tagged and can be tracked on http://www.seaturtle.org/ .This site provides free sea turtle tracking data around the world and you can even adopt animals that have been rescued and/or rehabilitated, as I did for our aquarium department for Christmas. Our previous turtle “Virginia”, released in the fall of 2010, was tracked heading northward 213 Kilometers in less than a week!



Our current turtle went on exhibit a few weeks ago and is still adjusting to life with many large fishes, at some point it too will be returned to NC and released back into the wild.


Saturday, March 12, 2011

Calico Box Crab

Calico Box Crab (Hepatus epheliticus) Molting:

We maintain a large collection of crustaceans and at least one of them molts each week. Usually it’s a blue crab (http://www.chesapeakebay.net/blue_crab.htm)
as we have many of them, but sometimes it’s something less common such as the lobster; it is fascinating to witness but unusual to catch in progress. This can be a dangerous experience for crustaceans as they are soft and exposed during this time and must be able to fully extract itself by themselves from the old shell; excellent water quality and a proper diet are essential to new shell formation.

Recently, I was able to film a calico box crab - a very attractive and docile crab species – in the process of molting as another crab watches in the background. In only about ten minutes this crab emerged about 20% larger, with a bright new shell. In a few days it will be fully hardened and eating again.

Follow this link to watch the calico crab pulling from its old shell:



Thursday, March 10, 2011

Lemon Sharks


Deciding when (and if) to introduce new animals to an exhibit is critical to their long-term success and the success of their tankmates. Animals that get large and may be dangerous to staff or other animals take considerably more consideration. I recently acquired two lemon sharks (Negaprion brevirostris) from Mystic Aquarium (http://www.mysticaquarium.org/) that are slated to go into our Chesapeake Bay exhibit within the next few weeks. Just getting them here was a challenge in itself, but more on animal transport later.

have the potential of reaching up to 12 feet and have a moderately aggressive nature. These two young males, “Sippy” and “Citron” are already pretty feisty. The following feeding video was taken only a few days after transport:

video


These two get very excited at feeding time and already have attacked several tank-mates, including each other! In just a year or two these sharks will become the dominant animals in this exhibit and I must consider this fact, including their potential aggression towards divers as well. We dive weekly in this exhibit and must be able to safely conduct our work; fortunately we are much larger than them – for now! At some point however, these two animals will get very large and may become aggressive towards us, the other fishes or even our loggerhead sea turtle.

Below is a podcast providing a brief background on lemon sharks and where/how I acquired them:
http://www.archive.org/details/VirginiaLivingMuseumAcquiresTwoLemonSharks

Wednesday, March 9, 2011

Jelly collecting

Culturing jellies for public display is labor intensive and time-consuming. Most aquariums display jellies and many public facilities have a full-time staff just for this purpose. As I write this, two staff members are out to collect jellies; not the species we usually cultivate and display at the VLM http://www.thevlm.org/jellyfish.aspx, the moon jelly (Aurelia aurita), but a local cold -water species common this time of year, the lion's mane jellies (Cyanea capillata) . Unlike moon jellies, the lion's mane jellies have a noticable sting, are more difficult to maintain, and eat each other on exhibit, making them less than ideal to care for. 

But they are currently everywhere in the rivers - and they are beautiful (above picture by Chris Crippen, VLM jelly exhibit) - making the opportunity to display them simply too good to pass up. As the weather warms, they will head out of the Bay and its tributaries, but for now they are an interesting change for our exhibit.

So how do we collect these jellies? With buckets. Yeah it's low-tech, but it prevents any damage to the jellies, damage that is usually done by lifting their fragile bodies from the water with a net or seine. Also it is a simple method to avoid physical contact with them because even broken off tentacles can carry an irritating sting. Lion's mane jellies are a little more work, but worth it.

A good on-line source of information about all aspects of jellies can be found at http://www.jellyfishfacts.net/. Chad Widmer, the former jelly expert at Monterey Bay Aquarium wrote a useful book entitled How to Keep Jellyfish in Aquariums: An Introductory Guide for Maintaining Healthy Jellies. The book does not fully cover professional level information on life support systems, but provides excellent feeding and propogation techniques and about every jelly species available, and is more than enough for almost all applications.

The following video is of the VLM's lion's mane jellies on exhibit now:
video

Thursday, March 3, 2011

Diving In

As a lifelong fish enthusiast, I will use this space to share what fascinates me about fishes, with an emphasis on topics relating to saltwater and freshwater (and those in between) fish species in Virginia and the Mid-Atlantic region. I hope to be an informal educational resource for those who may be interested and provide any insight I can from my professional and personal experiences.

I do not profess to be an expert and urge everyone to consult many sources, especially non-internet sources (although many are excellent) such as books, periodicals, and scientific research materials on topics relevant to the individual's needs. That being said, I have raised, caught, bought, bred, observed, photographed, released, drawn, painted, written about, read about, been bitten by, barbed, stung, cut, slimed by fish for nearly 35 years, which gives me some unique insight. I also professionally collect, raise, and care for literally thousands of fishes - marine and fresh - including sharks and sea turtles housed in over 200,000 gallons of exhibits and life support systems at a public facility. Additionally, I worked for several years on many long-term scientific finfish research projects and surveys ranging from american eels to bluefish.

But my true hope and intent is to inspire the reader to care for not only fishes but their habitats as well. There is little I would rather do than to be exploring for darters in a mountain stream or snorkeling on a jetty or around piling looking for blennies or filefish. Getting out there and having personal experiences is the goal, learning about what you see then comes naturally and brings the experiences to life again and again, long after, or until you can go out again.