Saturday, May 9, 2015

Seahorse genetics project

        The VLM is part of the lined seahorse SSP (Species Survival Plan), as part of the goal to "cooperatively manage specific, and typically threatened or endangered, species populations" by breeding seahorses at our facility and sharing/exchanging surplus with other institutions involved in the SSP. A major part of any SSP is research and the sharing of information regarding the species as well. Researcher Nancy Ho of the Vero Beach Marine Lab at Florida Institute of Technology heads a project that investigates the population dynamics and genetic diversity of lined seahorses in the wild; a project the VLM supports financially and helps to provide DNA samples from wild seahorses native to our area. 
A male seahorse (notice the pouch) is measured just prior to a fin clipping

        Whenever we are in the field and capture a seahorse, we record our collection location (co-ordinates, body of water) and retain the animal to get a tissue sample when we get back to the VLM. These wild sea horses have their own holding system specifically for this project, so they do not mingle with our captive bred population to insure that we can identify them as wild caught and that they don't interbreed. 


video
Sea horses like to stick together; here 8 of them lock tails on one small plant


        Samples are taken in a painless and non-invasive manner; we simply clip a 2 mm portion off the dorsal fin and save the fin clipping in ethanol. The entire procedure takes less than 30 seconds, causes the animal no pain, no loss of blood, and will grow back in a matter of weeks. The fin clipping is then sent to FIT, where Nancy can extract the DNA and determine what population the sea horses are part of. The wild seahorse can then be released back into the wild. Thus far we have submitted 17 samples for analysis and will hopefully be able to provide many more samples for her research.


Note the long fleshy appendages on their heads and along the backs

        Meanwhile the teenagers from our captive bred population are getting larger each day. They have graduated from Cyclopeeze and artemia to chopped mysis as well. this particular batch is extremely "branchy"(see picture and below); lots of long fleshy appendages, especially around the head. When these teenage horses are large enough and are trained to eat whole mysis from a feeding station, we will put them on exhibit. 
                                                            
Some of these guys are very ornate











                                                                                
                                                                                                                                     

Friday, May 1, 2015

Ruby Throated Hummingbird

Yesterday morning, animal keeper/trainer Carrie Bridgman found a lethargic and seemingly dazed  ruby throated hummingbird inside the River Otter exhibit. She brought the beautiful little creature inside our husbandry building to allow the otters into the exhibit without them having contact with it.  

It was immediately sheltered in a bucket with a baby blanket inside and another covering the top to give it some peace to rest and to hopefully allow it to recover enough to be re-released as soon as possible. I have experience with hummingbirds and volunteered (who wouldn't?) to monitor it's health. The first step being warmth on a cool spring morning and re-hydration - if necessary. As I prepared some warm sugar water for it, I heard it stirring inside the bucket. Knowing the fragile nature of this species and following the first rule of animal care - first do no harm - I wanted to make sure it did not injure a wing, so I immediately took it to a protected outdoors area behind the museum  in case it began to flap around or hopefully fly away; avoiding an injured or broken wing is the immediate concern. The hummingbird was going no-where for the moment, and simply rested with eyes closed. I then wanted to offer some water/sugar mix from a 1 cc syringe in case it needed some fluids. Aquarist Patrycja Lawryniuk thankfully was able to capture the little fella on camera. 

Just out of the bucket; a little subdued but content

It began to take solution slowly at first, but then very greedily. Thankfully the late spring sun came out just at the right time.

The refreshments and warm sun called for a short nap 

After 15 minutes or so of intermittent rest/feeding, it become much quicker moving and more alert. Eventually it took no more solution, looked around rapidly and flew into some nearby columbine.

It seemed to gather strength and become more alert minute by minute...

It then fed in nearly every flower for several minutes...

 flitting around faster and faster, and then it was gone, after a brief but ultimately successful encounter that I wont soon forget. 






Friday, March 6, 2015

Our new "Oyster Reef Ecosystem" exhibit: striped burrfish, blennies, skilletfish, spider crabs, etc.

Oyster reefs are one of the most productive habitats in the Chesapeake Bay; hundreds of species of aquatic plants and animals grow on and among their shells. The oysters themselves improve water quality and clarity by filter-feeding sediment and plankton out of the water while the natural accumulations of oysters that have settled upon the shells of their previous generations - essentially what constitutes "oyster reefs"- also serve as natural breakwaters that protect shorelines from erosion.

video
A live oyster reef 
Last April, we partnered with Professor Russell Burke of Christopher Newport University to help him construct one of many artificial reefs he has installed throughout the Bay to help promote settlement and growth of the American Oyster in the wild. Wild oyster populations in the Bay are at an all-time low due to decades of over-fishing. The most critical current obstacles to their recovery are excess nutrients and excessive siltation that smothers the reefs and spat - or young oysters. By placing specially designed concrete "castles" and "diamonds" in strategic positions, spat can settle above the mud, and can now build one-on-another in an ever expanding reef.

"Before" Oyster castle with no oyster growth

"After" Colonized oyster castle

Last month, we constructed an exhibit to represent the "before" and "after" of an artificial reef. The left of the exhibit displays an unsettled diamond while the right side displays a diamond from an artificial reef Dr. Burke placed in the Bay seasons ago; the results are striking. Every square inch of surface area on the "after" diamond is completely covered in massive adult oysters and mussels, as pictured above. All of these shells in turn host: sponges, bryozoans, algae, amphipods, isopods, worms, crustaceans, and a large variety of fishes. It is a complete ecosystem in miniature!

the fishes living inside the oyster reef, 

along with feather blennies Hypsoblennius hentz.

Naked gobies Gobiosoma bosci live in the nooks 
and crannies of the reef.

picking at invertebrates in the oyster reef. 
Grey snapper Lutjanus griseus are effective predators of 
smaller fishes and inverts.

Oyster toadfish Opsanus tau are a stealthy ambush predator 
that often bury in substrate beneath the reef. 

Like the oyster toadfish, mantis shrimp Squilla empusa will hide in tunnels 
  they've dug around the rock, and ambush any prey that come along. 
Hermit crabs (long clawed on top, striped below) are 
very common scavengers in oyster rocks. 

himself with pieces of a beard sponge to blend into its environment. 

By displaying the tangible results of the restoration work, and the richness of the species that rely on them - not to mention the commercial worth of the oysters to humans - we are displaying what is at stake besides the fate of the oysters themselves: the health of the Chesapeake Bay. Once known for its natural riches, it is increasingly known for being a system badly out of balance; a system in which the American oyster once lay at the very heart.

Saturday, January 10, 2015

Lion's Mane Jellies video Cyanea capillata

The VLM displays a variety of jelly species: moon jellies, sea nettles and lion's mane. Fortunately for us, we are surrounded by the Chesapeake Bay and its tributaries. Several species of jellies are native here and tend to follow salinity and temperature conditions that best suit them. because of the large seasonal fluctuations and the different preferences of different jelly species, each season is dominated by one main species. Winter in the bay is prime time for lion's mane jellies. When the water temperature dips below 50 degrees F - usually by mid-December - they appear seemingly out of nowhere.
video
A large lion's mane jelly in our exhibit

Lion's mane jellies have many long hair-like tentacles

Ice coats the jetty below the Coleman Bridge, Yorktown, VA

But actually their ephyrae, or juvenile form had already arrived and has been feeding and growing, morphing into the full blown medusa or adult jelly stage that most people recognize. The adult species of lion's mane jellies that frequent our area rarely get larger than a foot or so across and several feet long (still a big jelly), but in other parts of the world, lion's mane jellies can grow a bell over 6 feet across with tentacles stretching over 100 feet - the largest jelly species in the world! 


This lion's mane jelly on exhibit has a 5 inch bell and tentacles ~ 16 inches long

Each winter we anticipate arrival of the lion's manes and carefully monitor water temperatures in the nearby York River. We also have a network of members, staff, and volunteers of the VLM that report when they begin to see them. Perhaps the only jelly collector most people have ever heard of is SpongeBob SquarePants, but our staff is also out there with specialized "jelly" nets ready to collect wild jellies to augment our live collection throughout the year. Because of their size and beautiful colors, lion's mane are particularly desirable for exhibition. Unfortunately, January can be pretty cold on the water and this week was especially brutal. With air temps in the teens and wind chill near zero, it had better be worth it - and it was. We caught enough wild jellies to switch our exhibit from primarily sea nettles to lion's manes and will continue to display them and collect them throughout the winter.

 Sea nettles are more recognizable because they are here in the summer and are known for stinging swimmers. They even have a NOAA website dedicated to predicting their presence inshore.

Moon jellies do have tentacles, though they are much shorter than either nettles or lion's mane

Ctenophores or comb jellies are harmless and often luminesce at night

Like most jellies, lion's manes use their stinging tentacles to ensnare and subdue prey. In this area, they feed on virtually anything that becomes entangled in their tentacles as they flow behind the travelling jelly; it could be anything from zooplankton to small fishes. Here at the VLM we hand feed them daily a mix of Artemia nauplii and diced seafood such as shrimp, squid, or scallops. They will be on display throughout the winter and spring, when we will start gearing up for sea nettle season.






Saturday, December 6, 2014

Baby pipefish - video

video

Seahorses are instantly recognizable, but few people have ever seen or even heard of a pipefish. In fact there are three species of pipefishes in the Bay, and they are quite abundant. Northern, dusky and chain pipefishes all are found in the same general habitats in the Bay and coastal ocean: shallow, low-energy grass beds, or near-shore vegetation. Their unique coloration and elongate "pipe" shape - essentially a straitened out and stretched seahorse - gives them an uncanny ability to disappear among vegetation. Coloration can vary widely from dark brown to vibrant green, and they may be solidly colored or distinctly banded, which is more often the case with chain pipefish.

A pipefish tries to blend in 

Through camouflage and patience, pipefishes remain motionless and (hopefully) undetected waiting for unsuspecting prey to wander by. They also actively stalk prey by slowly and stealthily gliding through dense vegetation, propelling themselves with rapid undulations of their small dorsal fin and pectoral fins. This minimal motion is difficult to detect and does not betray their stick-like or grass-blade disguise. Just like seahorses, pipefishes use a long protrusable tube-like snout to slurp up small crustaceans such as amphipods and isopods; in fact seahorses and pipefishes are often found in the same areas.

A seahorse and a pipefish hang out together on exhibit. 

Both pipefishes and seahorses share many physical characteristics. Their bodies are very similar, though their swimming and resting orientation is different; seahorses are upright while pipefishes are horizontal. Both have a trumpet-like tubular toothless mouths, small pectoral fins, elongate bodies made up of bony rings much more evident in pipefishes (see above), very small dorsal fins, and a leathery brood pouch on the males which is distinctive only to the Family Sygnathidae (both pipefishes and seahorse spp.). Pipefishes have a rayed - fin tail, while seahorses have a prehensile tail to hold fast to structure and vegetation. Both Sygnathids can be a difficult to keep healthy in captivity mainly due to their specific diet, nutritional requirements and need for an almost constant availability of food. Juveniles and wild-caught specimens often don't transition to prepared foods well - if at all -, as they are naturally ambush predators and stationary foods don't trigger any innate hunting or feeding behavior. They can eventually be trained to take a variety of foods and can even be trained to a "feeding station", a specified area where food can be placed in a concentrated amount. Adult pipefish usually feed very eagerly on non live enriched foods, such as Cyclopeeze and Mysis, and breed often when healthy.

A two day old pipefish hunts Artemia nauplii...

Compared to seahorses of similar age (born Dec 11, 2014)




Friday, November 14, 2014

Deep Sea Fishes and Inverts: A Look Into "Beyond the Edge of the Sea" Exhibit

There are no places on Earth more foreign to humans than the depths of our oceans. The extreme pressure alone prohibits any normal vehicle from exploring their depths; but add to that the sheer enormity of space - almost 80% of the Earth's livable environments by volume are below 1000m deep - coupled with complete darkness and we have only a small glimpse so far of what lies beneath.

A few years ago I was fortunate enough to assist on a project led by Dr. Tracey Sutton who studied deep sea environments post-BP Deep Sea Horizon Spill, that also included a former employee Sarah Peake (now at GA Aquarium) and colleague Wendy Mooring. As a parting gesture Dr. Sutton donated some deep sea specimens to the collection here at the Virginia Living Museum. We temporarily use them during educational programs and seminars but to this point have not displayed them to the general public. Until now!

Close up of a small deep sea anglerfish

In another fortunate happenstance, Director of the Duke Marine Lab, deep sea explorer, former College of William and Mary professor, and long-time Alvin pilot Dr. Cindy Van Dover will be here at the VLM on November 15th to share some of her experiences and showcase her exhibit "Beyond the Edge of the Sea". This traveling exhibit features deep sea life and scenes witnessed in person aboard the Alvin that are beautifully rendered in scientifically accurate water color by artist Karen Jacobsen. Portions of her artwork are shown below:


                                           

We took this opportunity to publicly display several of our deep sea specimens for the first time. Below are a few of the preserved animals that you can see here alongside the beautiful artwork.

A display case of strange deep sea fishes and invertebrates

Threadfin Dragonfish Ethiostoma barbatum

Sloan's Viperfish Chauliodus sloani

Chimera

Porcupine Crab

Saturday, August 30, 2014

Striped bass and striper hybrids in our James River exhibit

September is the month we do our major exhibit work, including fish moves. Our first priority is to release any animals that will be too large to keep until next spring and replace them with smaller animals that can be kept comfortably at least until next collecting season. The first exhibits to down-size were the James River and James River Shallow exhibits. Earlier this year we added yellow perch that had grown too large for the Yellow Perch exhibit, and walleye that were transferred from the National Aquarium in DC when it (sadly) closed.

Two year old yellow perch
A walleye in James River exhibit

But we also acquired some captive bred striped bass (~30) and hybrids (~ 12 white bass x striped bass) from a hatchery to replace the adult striped bass which are the signature species in this exhibit. These hybrid and striper juveniles were initially about 4 inches when we got them but have been growing rapidly in our James River Shallow exhibit. They are now large enough to replace the striped bass adults in the main exhibit which have grown too large for the exhibit and were released last week. Below is a video of the very active school of stripers and hybrids just put in the main portion of the exhibit.
video
Stripers and hybrids school in their new exhibit

It is difficult to discern the hybrids from the pure bred striped bass, especially in the video. Generally, the hybrids demonstrate physical traits of the white bass that differ from pure bred striped bass: a higher shoulder profile, more irregular stripes, and a darker back in adults. All three species, white, striped, and hybrid are very aggressive predators and grow rapidly. Next spring we will have to remove a portion of this school to make room as they grow and by next fall we may have to start the process all over again.

The iconic striped bass


A hybrid striper 
Striper above, hybrid below

The shallow portion of the exhibit has been thoroughly scrubbed, cleaned, re-decorated and re-populated with a variety of smaller fishes and plants from our collection including a new female wood turtle taking the place of the irreplaceable "Woody" who recently passed away of old age.

"Woody" was the mischeivious, charasmatic long-time resident male wood turtle in James River