Tuesday, December 31, 2013

New loggerhead sea turtle "Abe" is on exhibit - Video

The juvenile loggerhead we acquired in October from NC Aquariums is now on exhibit in our Chesapeake Bay Aquarium. The time between his acquisition and his exhibit debut on December 26th was well spent getting him (there actually is no way to tell the gender for many years) acclimated to his feeding schedule through target training. Because Abe now comes to the surface regularly to be fed and has grown accustomed to tank mates, he has graduated from the 1000 holding system to the 30,000 gallon exhibit. He not only has much more space to roam, but also has a much more stimulating environment.

As seen in the first video, Abe - like all our other sea turtles before him - loves to hang out and sleep in the "cave". Though the cave is natural rock we collected nearby, its base structure is an eight foot long acrylic aquarium with plenty of holes cut into is for many entry and exit passages. Abe shares the cave with our resident gag grouper, who has been at the museum for over twelve years.
Our gag grouper Mycteroperca microlepis in front of the cave
So far Abe has settled in nicely to his new home and exhibits no fear of his new tank mates. He has shown to be both calm and inquisitive; good signs for long term success. The videos were taken on a dive his first day on exhibit.

Tuesday, December 17, 2013

Mergansers eating live shiners in the swamp - underwater video!

One of the more interesting aspects of our Cypress Swamp habitarium is the variety of species; from the American alligator and several turtle species to over a dozen fish species. But that's just in the water.

The two-story glassed-in replica of a Virginia swamp also allows enough sunlight for live cypress and magnolia trees to thrive in which live birds make their homes. Brown thrashers, a red headed woodpecker and bobwhite quail can all be seen amongst the branches and boles. In the space between the land and water are our three mergansers. Comically awkward on land, these sleek waterfowl are master swimmers. Their bodies are squat with very rearward legs, making them waddle on land but virtually fly underwater - almost like a penguin bent forward. In the wild, mergansers chase down crayfish, frogs, salamanders and any species of fish small enough to swallow.

Three mergansers easily chase down golden shiners in our Cypress Swamp

Thankfully, most of our fishes are so large, the mergansers pose no threat. In fact, some of the fish species we feature - including the gator - are large enough to turn the tables on an unsuspecting bird or duckling given the opportunity. Both largemouth bass and channel catfish grow large enough and are capable of inhaling large prey items. These adult mergansers however are in no danger, not only are they too large for the fishes, but are too fast and armed with a beak that can discourage even the most aggressive bass. 

Saturday, November 9, 2013

Loggerhead sea turtle training/feeding

This video shows the new turtle learning to feed in her new enclosure at the VLM

Before a new sea turtle is introduced into our Chesapeake Bay Aquarium, we must first ensure (among many other things) that it will be able to acquire food regularly and be accessible to staff. The most common practice is to "target train" them or condition them to associate visual - and often audible - stimuli with food. Fortunately, NC Aquarium had already begun process of training our current turtle to feed regularly from tongs. However, new surroundings have required our new turtle to learn a new routine and feeding schedule before it can safely go into CBA. We began by simply acclimating the turtle to a regular daily feeding at 2 pm daily; this coincides with the time it would be fed when in CBA. As the turtle has become accustomed to staff and its new schedule, we have introduced the visual stimuli - simply a blue Kydex disc on an algae scraper - at each feeding. The new turtle has slowly become accustomed to seeing the target and has begun to equate the presence of the strange blue disc with the magical appearance of food. Eventually, 2 pm = feeding time, target = location of food and we all settle into an efficient and reliable routine.

 A small hand target is placed in the water prior during each feeding
 A sampling of natural foods that the sea turtle gets along with commercial gel diet and supplements
 The new turtle comes up to check out the target prior

One more side note: I like to introduce fishes in the turtle's enclosure as early as possible. First and foremost, the turtle will be amongst much larger fishes in CBA and its beneficial to get it accustomed to the distractions of many fishes. Secondly, the fishes often attempt to steal food from the turtle, as they will on exhibit, so the turtle will begin to actively compete for food and not be startled when it is placed in CBA. And lastly, it gives us a good indicator of the turtle's personality and aggressiveness - or lack thereof.

Wednesday, October 23, 2013

Loggerhead sea turtle release videos - Gulf Stream

After we permanently transferred our unreleasable adult loggerhead sea turtle "Christi" to a larger exhibit at Dallas World Aquarium in 2009, we began to partner with NC aquariums to acquire juvenile sea turtles that we could display for three years and then be released back into the wild. The previous two sea turtles we have displayed at the VLM - Virginia and Abby - have originated from the North Carolina Aquarium at Pine Knoll Shores, including the most recent juvenile (unnamed as yet) we acquired on our trip to release Abby.

A sea turtle nest roped off in Duck, NC

NC Aquariums has an excellent support network of volunteers and trained staff that monitor loggerhead nesting sites along the coastal beaches. They not only protect the nests from being disturbed, but assist the hatchlings to reach the water safely and collect valuable data in the process. The vast majority of hatchlings emerge from the nests healthy and able but many hatchlings do not successfully extract themselves from the nests and may remain buried unless assisted. Once the hatchlings have vacated the nests on their own, the nests are excavated for the stranglers which are then brought back to the aquariums to be nursed back to health or held until they can be released.

A bin of loggerhead hatchlings ready for release by the NC Aquarium

A few of the rescued juvenile turtles are loaned out to other public facilities to serve as educational ambassadors in such places as: Pittsburgh Zoo and PPG Aquarium, Newport Aquarium, Mystic Aquarium, Monterey Bay, and the VLM. Some facilities display the turtles as juveniles and return them after one year; we display the animals for up to three years and then return them to NC for release, and in "Abby's" case, to be affixed with a satellite tag.

Above: VLM Aquarist Patrycja Lawryniuk attaches the satellite tag with epoxy
Below: Close up of the tag that will transmit Abby's location when she surfaces

Just last week we joined these other facilities and their sea turtles at Pine Knoll Shores to release our sea turtle "Abby" along with the others back into their native waters. This time of year the water has begun to cool, so we chartered a SCUBA boat from Discovery Diving  in Beaufort, NC that took us 36 miles offshore in search of warmer Gulf Stream waters. After a three hour boat ride we took turns releasing these beautiful, prehistoric creatures out into the wild. One by one, each facility had the honor of releasing the turtles in their care back into the ocean. Fortunately, I brought along a wet suit and small underwater camera to capture the releases on film.

A hatchling at release


The ocean can make one feel very small, especially untethered miles and miles offshore. The expanse seems infinite. But sea turtles are here after all these millions of years because deep within them lies the knowledge and instinct to survive out there, to find food, to find each other. As Abby glided off into the emerald sea far beyond my reach and out of site, in the last few seconds I would see her - after seeing her and caring for her daily for three years, I caught the final glimpse of who she really is and what she is meant to do; a small thing really. She flapped briefly to gather speed, to test her freedom and then spread her back flippers and glided with the current, slipping weightless, riding the powerful current to some unseen destination with no hesitation or fear.

As of 10/24/2013, Abby has traveled a total distance of 693km (that's about 430 miles!)! You can follow her progress at http://www.seaturtle.org/tracking/?tag_id=128947

Saturday, October 5, 2013

Redbreast sunfish fry development

A large male redbreast Lepomis auritus in breeding colors

The term "sunfish" generally refers to fishes from the Family Centrarchidae, comprised of 30 species (including several bass species and crappie), but to most people "sunfish" are species from the Genus Lepomis: bluegill, pumpkinseed, longear, warmouth, redear, green, and redbreast sunfishes. To further complicate matters, Lepomis species can - and often do - hybridize with each other especially in captivity (see below). 
 A large male pumpkinseed/redbreast hybrid Lepomis gibbosus on his nest

Most sunfishes spawn in early to mid summer, when the water temperatures begin to approach 70 degrees F. However, in captivity many species - not just sunfishes - are triggered to spawn at unusual times of the year, due to unnatural light cycles and seasonal temperature fluctuations within the facility. For example, two species of sunfish in our Woodland Pond exhibit, the pumpkinseeds and redbreasts are currently spawning, but are several months past their spawning period in the wild.

Breeding or "nuptial" males of all sunfish species fan out broad, saucer-shaped nests with their tails in hopes of attracting a female. The males then aggressively guard these nests which are often quite close together, and chase off all intruders. During this period males become brilliantly colored, showing off their best and brightest for the ladies. If the male successfully attracts a mate, he will fertilize from 1000's to 10's of thousands of eggs, depending upon the size of the female (and species), which she has deposited in the nest. After releasing her eggs, she moves on with no further commitment to the young. The males remain to guard their young from predators as the young develop from eggs to yolk sac larvae to free-swimming larvae. Once the young are swimming and feeding on their own, the job of the male is finally done.

 Eggs are approximately 1 mm

Redbreast fry that have just lost their yolk sac

Fry one week later ( 2 -3 weeks total)
...another week older (4- 5 weeks)
Fry seven to eight weeks after hatching.

Friday, September 13, 2013

Brook, rainbow, and brown trout feeding frenzy

This first video was taken today during our 11 am trout feeding program the Mountain Cove Exhibit. The main exhibit has three distinct sections: brown trout (immediately below the waterfall), the mountain stream (home to darters and dace, including the P. rex), and this portion which is a combination of approximately 14 each of rainbow trout and brook trout. The trout are fed GrowMax trout chow every M, W, F, Sunday during the public feeding and a variety of natural foods on the days in between. Each section, including these trout, breed at least once a year. In fact, the largest female brown trout released eggs this morning. We generally do not collect and raise the eggs - the trout eat them otherwise - unless we have a specific need, but there are both brooks and rainbows currently in this exhibit that we raised from eggs a few seasons ago.
The second video is of the brown trout feeding. The largest female is approximately 12 pounds and is over nine years old.

Wednesday, September 11, 2013

Roanoke logperch in the wild - rare underwater glimpse of them in the Nottoway River

This video of  Percina rex in the wild was taken from the Nottoway River, a relatively pristine tannin-stained river that forms the headwaters of the Chowan drainage system. The Nottoway is exceptionally rich in species of fishes and quite beautiful as well. The footage is of a single, large adult Percina rex in its natural habitat and was one of four different Roanoke logperch of three size classes seen at this location.

 Three male P.rex encircle a single female vying for the chance to mate

The Roanoke logperch Percina rex is one of Virginia's largest and rarest darter species; currently listed as Federally Threatened and Endangered since 1989. Thanks to the US Fish and Wildlife Service and the Virginia Dept of Game and Inland Fisheries we have been fortunate enough to display several of these beautiful creatures here at the VLM. Our P. rex population, housed in the Mountain Stream Exhibit has been thriving and has displayed natural mating behaviors on several occasions - a sign of healthy animals in an appropriate environment. They are excellent display animals because they are large - for this type of fish - colorful, and remain in the open for the guests (and staff) to see and enjoy. But due to such small numbers in the wild, only researches, biologists, and lucky darter nerds get to see them in their native habitat.

 The roanoke logperch (center) on exhibit are not shy when it comes to food

Saturday, August 10, 2013

Mantis shrimp (Squilla empusa) video

The mantis shrimp is a very strange creature. It is a highly predatory arthropod with one of the most complex compound eyes in nature, each of which can not only see independently, but also can detect colors throughout the entire spectrum of light; their unique eye structure also allows the mantis shrimp to see in 3 dimensions. Add to their incredible eye sight two powerful claws that can strike prey with speeds as fast as any animal movement on earth and you have a very formidable predator. In fact, the mantis shrimp is named for its "praying mantis" like claws that they extend with such force, they can shatter the glass of an aquarium! 

A close up view of the mantis shrimp's complex eyes

Mantis shrimp utilize their assets well; they are reclusive burrowers that use their broad tails to excavate a burrow in which they lie in wait for prey. As an unwitting victim wanders by, the mantis shrimp uses a lightning fast strike to capture and kill its prey. These animals are also known as "thumb splitters" for their effect on people who do not handle them with care. This particular animal was captured in a trawl off Beaufort, NC during a collecting trip. It cannot be housed in our "shrimp" exhibit with the true shrimps, the commercially important food species of brown, pink or white shrimp from the Genus Penaeus (pictured below) because it would easily feast upon its more passive tank mates and ultimately be the last shrimp standing.

The brown shrimp Penaeus aztecus is a species of true shrimp

Saturday, July 27, 2013

Juvenile sandbar sharks - video!

We recently acquired two sandbar sharks (Carcharhinus plumbeus);one male and one female. They are in quarantine at the moment and may not be on display for a while, but this video provides a sneak peak. The smaller of the two is a female and likely only a couple of months old. More about where/how we got them, details about their care, and what we have planned for them very soon...

Saturday, July 13, 2013

Blenny fight! A dominant male protects his food (little neck clam)

A dominant male (blue spot on the dorsal) fights others away from the freshly shucked clam in our piling exhibit

Feather blennies are named for the two cirri or "feathers" over their eyes

Blennies, feather blennies in particular, are feisty little fishes (as seen in the video). Blennies are a group of small saltwater fishes that remain around relatively shallow water structure, such as oyster reefs and pilings throughout their entire lives. Once they have established a territory, they vigorously defend it and often battle each other in close quarters for food and mates. Productive habitats may house a blenny or mated pair of blennies every couple of square feet, each patrolling their respective property with head up and fins extended ready to scrap. One reason they defend their territory so aggressively is that prime real estate is hard to come by and even harder to get to. These pugnacious little fishes are not strong swimmers, rather they rest upright on their broad pectoral fins and use their broad rearward fins to propel them quickly forward in lightning fast bursts - usually at a trespasser on his territory - and not for long distances.

Striped blennies often lay on their sides inside seashells

There are a few other species of blennies occasionally found in Virginia, but the most common by far are the feather blenny Hypsoblennius hentz, and the striped blenny Chasmodes bosquianus. Though these two are related, the striped blenny is a much less aggressive species and therefore easier to house in an exhibit with other species. They often are found in proximity to each other and a host of other species as well.

Naked gobies can often be found with blennies among oyster shells

Oyster reefs and grass beds are important habitat for a huge variety of similar fish species such as the naked goby, skilletfish (above - pictured stuck on the acrylic with a "suction cup" on its belly) and the much maligned oyster toadfish (a pile of them pictured below)

 Innumerable crabs and shrimps also hide in the nooks and crannies of the oyster shells. 
 Grass shrimp, sometimes called ghost shrimp are an important prey species

All these animals occur in such densities because there is an enormous amount of prey and forage items available in these areas, mainly invertebrates and algae. These structure communities in turn attract a multitude of predatory fishes attracted to a high concentration of prey. Fisherman may not be aware of exactly why oyster reefs draw sea trout, red drum, croaker and stripers, but they certainly know that they do. We attempt to represent these structure-based communities in our "Piling" exhibit that showcases blennies, gobies, skilletfish, sheepshead, scup and a variety of crab species.But as noted earlier the feather blennies rule the tank, nipping at fins and challenging much larger fishes, making it difficult to display more than a dozen or so fishes at a time.

Tuesday, July 9, 2013

Video of "teenage" lined seahorses (H. erectus) feeding

Our "baby" seahorses are growing up. Since they were born several months ago, each of these lined seahorses has grown considerably and they have all begun to take on individual characteristics. As seen in this video, they display a wide variety of colors, patterns and even sizes. Lined seahorses use their colors, elaborate patterning and fleshy appendages to hide amid submerged aquatic vegetation (SAV) which were once much more common and wide-spread throughout the Bay. Micro-communities live in and actually on the leaves of aquatic vegetation - called epiphytes - that support and house a surprising number of small organisms, especially amphipods, and a variety other small invertebrates upon which seahorses feed.
In captivity they are fed enriched P.E. Mysis, live Artemia and Cyclop-Eeze throughout the day.

During the next stage of development these adorable little fishes will begin to mature sexually and we can then finally tell how many males and females were born. Seahorses are sexually dimorphic - males and females are physically different externally - and the male can be discerned by a large leathery brood pouch on the front of his torso. These animals are part of the Line Seahorse SSP (Species Survival Plan). The VLM and many other zoos and aquariums across the country within the AZA community captive breed and exchange lined seahorses to ensure they are genetically diverse and that there will be no need to capture any wild lined seahorses for display. Look for some of the larger juveniles to finally go on public display with the four adults (pictured below) already on display in our seahorse exhibit in the Chesapeake Bay gallery.

Seahorses like to hang around together

Saturday, June 29, 2013

Jellies - by Aquarist Patrycja Lawryniuk

Jelly hunting is an work activity that I enjoy the most! Every year the aquarium staff collects jellies from the local waters near to the VLM, such as the York River. Certain jelly species are seasonal and tend to show up in the area at different times of the year. The large colorful lion's mane jellies Cyanea capillata are actually arctic and prefer colder water, and therefore appear in late January to early March. The white jellies that haunt the summertime waters are sea nettles Chrysaora quinquecirrha, which are famous for their stinging tentacles. We can usually rely on sea nettles popping up in early June when the waters start to warm up. However, an unusual amount of heavy rains have kept water temperatures low and pushed their arrival back a few weeks. Since sea nettles are so common in the Chesapeake Bay, the National Oceanic and Atmospheric Administration (NOAA) tracks the ideal conditions for these jellies in the bay, and we are able to view their abundance online!  Finally, in the last two weeks, we hit the jelly jackpot at Grandview Beach in Hampton.

Sea nettles are generally much smaller than lion's mane jellies, but are faster and more aggressive. Their sting can be deadly to their prey, but is no more than a painful irritation to humans and can be neutralized with a small amount of vinegar. Nettles are carnivorous, usually feeding on zooplankton, other jellies, and even small fishes! On exhibit we try to emulate their natural diet as closely as possible. They are fed minced  capelin, shrimp, or squid, with an enriched commercial food called Cyclop- Eeze The prepared food is then mixed with salt water and distributed to each jelly using a turkey baster. Lion's mane are larger and slower, and their sting is not quite strong enough to irritate human skin, therefore they are fed with larger pieces of food which is distributed individually into their tentacles using tweezers.Moon jellies are planktivorous and are fed Artemia nauplii or newly hatched brine shrimp.

Saturday, June 22, 2013

Saltwater collecting season: juvenile lookdowns, sea robins, flounder, etc.

 A summer flounder (~ 2 inches long)

As the weather warms up, the aquarium department takes full advantage of our brief opportunities to catch all the saltwater fishes we will need until next year. Early summer is an excellent time to collect, not only because of the weather; a wide variety of juvenile fishes frequent the shallows as they begin to prey on invertebrates, micro-crustaceans and larval fishes close to shore. These miniature predators are voracious and eat constantly to fuel their rapid growth. Come fall they must be large and healthy enough to survive among the big boys when they will either migrate southward or move into deeper water. During the summer we are able to collect a wide variety of species: summer flounder, lookdowns, puffers, sea robins, black sea bass, jacks with a beach seine, sometimes in the same haul! Many of these species would be much more difficult to acquire as adults, so we seize the opportunity to catch them while we can. There are several benefits to collecting fishes as juveniles - other than convenience - but most importantly juveniles acclimate to captivity much more readily than adults. Below are just a few of the juvenile fishes we collected this season with (hopefully) many more to come.

Juvenile bluefish

 Juvenile lookdown (approximately the size of a quarter)

Juvenile sea robin
Juvenile northern puffer
Juvenile black sea bass

Saturday, May 25, 2013

Candy darters (Etheostoma osburni) in Big Stony Creek

Below is a short video of the elusive candy darter, native to the New River drainage.

Virginia has an excellent variety of native fishes primarily due to the diversity of aquatic habitats. Several large Chesapeake bay tributaries begin on the eastern slope of the Appalachians as cold upland creeks, gaining volume and strength before emptying into the Bay. Headwaters may begin as a native brook trout stream but their ecology may change drastically, ultimately ending up (like the mighty James River) miles across and home to oyster reefs and a variety of saltwater species. But many Virginia rivers and streams do not end up in the Bay. In the western portion of the state, several large rivers - the North and South Forks of the Holston, the Clinch and the Powell - are part of the Tennessee drainage, while the ancient New River flows northward into West Virginia and becomes part of the Ohio drainage. The Roanoke River flows southward into North Carolina and ends up in Albemarle Sound. 

Roanoke logperch are native to just a few small sections of water in Virginia

Each of these rivers and drainages have a unique geological and cultural history, but also have fish species unique to them alone.Unfortunately, many of these species have evolved to rely upon their specific habitats within these rivers. Over time they may become isolated in an ever shrinking portion of habitat within their native rivers. An excellent example of this is the Roanoke logperch; this Threatened and Endangered species suffers primarily from habitat loss and degradation related to human activity along the banks of the Roanoke. The constriction of habitat often begins the slow doom of such creatures that literally have nowhere else to go. Not only are these fishes in jeopardy, but the cold, pristine streams they require is also getting harder and harder to find.
 The candy darter Etheostoma osburni is truly eye candy to native fish lovers

Recently Nick Little, Senior Aquarist for the National Aquarium in D.C. and I went in search of one of the rarest and arguably the most beautiful of all the darters, the candy darter Etheostoma osburni. This darter is native only to the New River drainage and is found in such limited areas and small numbers that it is listed as a Species of Special Concern, and is protected by law. We were driven by the desire to see these beautiful animals for ourselves, alive in their own habitat before they are gone. This may sound dramatic, but each year at least one spot I have previously enjoyed has been bought, bulldozed, or altered in the name of progress.

A pristine tributary of the New River

Although we are prohibited from collecting or displaying this species, as darter enthusiasts (nerds) the challenge was to find them, and then film them underwater.Unfortunately for us, they like gravelly beds in swift water, so our videos reflect the fact they are far more suited to such habitat than a couple of dudes in wet suits with one hand on a camera and 50 degree water flowing down your front.
Nick finds his soul mate; a female candy darter resting in the depression atop this rock
A male candy darter in the photo box

I put one of the photo boxes into action

Aside form the obviously beautiful candy darter there were many other excellent fishes, among them: the fantail darter, the Appalachia darter, mountain redbelly dace, an extraordinary population of crayfish, and the crescent shiner.
Appalachia darters are also native only to the New River system

Saturday, May 18, 2013

Seahorse breeding tank - babies meet parents!

Today we removed the partition that separated the lined seahorse parents from their young and they mingled together for the first time. The partition protected the young from being sucked against or into the filter system. As the video shows, the juveniles are two different ages; about three months apart. Seahorses love to cling to each other with their tails and often form chains of three or four seahorse all connected together, often attempting to move in different directions at the same time. In the above video they are feeding on live adult Artemia or brine shrimp, which they get many times a day, but also are fed Cyclopeeze and Mysis. Its easy to tell from the video why people like seahorses so much; they have a gentle and inquisitive nature - and are just a bit silly.

Saturday, May 11, 2013

White catfish (Ameiurus catus) spawning

This video shows a pair of our many white catfish spawning. These two have fanned out a shallow depression underneath some woody debris with their tails. They perform a ritual where they swim in circles side by side until they eventually are ready to mate. They press their sides together head to tail-tail to head and curl their tails around each other. They do this repeatedly for several hours: she deposits eggs and he fertilizes them.
A pair of white catfish

Catfish inhabit nearly every aquatic habitat across the world; a testament to their adaptability and biological success. As a group, they are one of the most important commercial food fishes and also extremely popular sport fishes, so it is no wonder catfish are so recognizable. Many tropical species are also quite popular in home aquaria (e.g. plecos, corydoras). Catfish are very recognizable because of their "whiskers" for which they are named. These are actually sensory organs - external taste buds - that help catfish detect food with amazing sensitivity..

The pale to white lower pairs of barbels help to distinguish the white catfish.
Brown bullheads have dark barbels.

In Virginia there are fifteen species of catfishes from two major Genera: the forked-tail catfishes Genus Ictalurus, and the bullheads Genus Ameiurus to which the white catfish (Ameiurus catus) belongs; within Ameiurus the subgenus Noturus contains six small stream species of catfishes called madtoms. White catfishes are the largest of the bullheads and, unlike the larger forked-tail catfishes, are native to Virginia. 

Brown bullhead Ameiurus nebulosus
Channel catfish (Ictalurus punctatus) were introduced in the late 1800’s, but the blue catfish (I. furcatus) and flathead catfish (I. puctatus) were introduced within the past fifty years, all as sport fish. Channels and blues especially have become so pervasive that they have out-competed the much smaller and less prolific white catfish in almost every body of water they share. 
This "white" catfish is actually an amelanistic channel catfish.