Chattanooga, Tenn. (May 9, 2019) - Thanks to the unexpected discovery of several clutches of eggs in the weeks leading up to Mother’s Day, the Tennessee Aquarium is practically bursting with mothers-to-be.
Husbandry staff began finding these surprise eggs in April. One of the first was the leathery case of an Epaulette Shark egg, also known as a “mermaid’s purse,” in the Ocean Journey building’s Stingray Bay touchtank.
Some species of sharks, including Bull and Blue Sharks, are viviparous, meaning they give birth to live young. Others, such as the Aquarium’s Epaulette Sharks and Coral Catsharks, are oviparous, laying eggs from which pups later hatch.
Senior Aquarist Kyle McPheeters shines a light through an Epaulette Shark egg case. The shadow of the developing pup can be seen moving.
Finding an Epaulette Shark egg isn’t entirely unexpected according to Senior Aquarist Kyle McPheeters.
While tending to the exhibit in late April, McPheeters discovered this egg under a rock pile and quickly realized a developing shark pup was inside.
“This one had been hidden well,” he says. “I wanted to be sure to take it out of the tank and transfer it to another space since it was clearly a fertilized egg with a shark growing in it.”
Now housed in a shark holding tank in the River Journey building, McPheeters says the egg’s size suggests the pup is about a month into its four-month incubation period. Based on his past experience with this species, he thinks the pup could emerge sometime in August.
An adult Epaulette Shark swims through the Stingray Bay touch tank. These sharks are known for their ability to "walk" along the seabottom or between shallow pools in pursuit of prey.
Epaulette Sharks are known for specially adapted fins that allow them to crawl along the seabed or across land to access the shallow pools where their prey live. This trick earned the species its nickname as “The Walking Shark” and earned it the distinction as a particular favorite of McPheeters, who raised about 90 of them for the Aquarium between 2012 and 2015.
“They’re way cool,” he says. “They’re what got me excited about raising baby sharks to begin with. It’ll be nice to have one again, and we’ll be able to send it to another aquarium pretty easily when it’s older.”
A clutch of five Barbour’s Map Turtle eggs rest inside an incubation container. Aquarists discovered the recently laid eggs in April in the Aquarium’s Delta Country gallery.
Another recent egg-citing discovery at the Aquarium was a nesting site found in the River Journey building’s Mississippi Delta Country gallery. Here, nestled amongst the vegetation, Senior Animal Care Specialist Jennifer Wawra found a clutch of five recently laid eggs believed to belong to a Barbour’s Map Turtle introduced to the exhibit last fall.
Identifying the species responsible for these ovular surprises will be difficult until they hatch, but based on their shape, staff herpetologists suspect the Barbour’s is, in fact, the expectant mother.
If the eggs prove to be Barbour’s Map Turtles, they will represent the fulfillment of months of planning and scientific matchmaking on the part of Aquarium staff. The male Barbour’s was acquired through a donation and introduced to the exhibit about a year ago. Six months later, the female was moved from another section of the Delta Country gallery to join the male in hopes of encouraging them to breed.
“We saw a lot of activity from other turtles in there trying to breed with the female Barbour’s, which we didn’t want,” Wawra says. “But when I went down there one afternoon, the male, who is about a quarter as big as the female, was protecting everything — her space, his space — and fighting off every turtle in there.
“I ran back up to our curator’s office and was like, ‘It’s going to work! They’re going to breed!’”
Light shines through the egg of what is presumed to be a Barbour’s Map Turtle in an incubation room. Vein growth visible inside the egg, which was recently discovered in an Aquarium exhibit, suggests healthy development.
The eggs, which were discovered on April 15, have been relocated to an incubator. Barbour’s Map Turtle eggs have an incubation period of 60-75 days, so Wawra says any hatchlings won’t emerge until mid-June or early July.
“Veins are developing in four of the five eggs, so hopefully, we’ll get some hatchlings,” she says, smiling. “We are very excited because this species is listed as vulnerable in the wild.”
In Penguins’ Rock, breeding season has been in full swing since the arrival of nesting rocks to the exhibit on April 1. Almost immediately after hundreds of pounds of smooth- and rough-edged stones were deposited in the gallery, the Gentoo and Macaroni Penguins began pairing off, building nests, and, in many cases, actively breeding.
On April 27, Aquarium staff members found the first egg of the season in the nest of Gentoo Penguins Bug and Big T. These experienced parents have successfully raised five of the 20 chicks that have hatched in the gallery since 2009, including the gallery’s newest addition, Big Foot, who hatched in 2017.
Gentoo Penguin Roxie looks down at her egg in the nest she built with her mate, Beaker, in the Penguins’ Rock gallery. The egg is one of several that have been laid by the Aquarium’s Gentoo and Macaroni Penguins in the last two weeks.
Since the first egg’s arrival, several more have appeared in the gallery, including a second for Bug and Big T and one each for Nipper and Pebbles (Gentoos), Roxie and Beaker (Gentoos) and Chaos and Merlin (Macaronis).
Normally, the first eggs don’t appear in Penguins’ Rock until later in May or even early June. This year’s quicker start was surprising, but it didn’t catch staff members off-guard, says Senior Animal Care Specialist Holly Gibson.
“The eggs came pretty early, but we were prepared for it,” she says. “We brought all their rocks on exhibit, and they immediately started building their nests. They had everything they needed, so I guess they were just ready to go.”
Macaroni Penguin Merlin sits atop an egg in the Penguins’ Rock gallery. The egg, which was laid by Merlin’s mate, Chaos, is one of several that have been laid in the exhibit in the last two weeks.
No penguin chicks hatched in 2018, so staff members and guests alike are excited at the prospect of new birds hatching this year, especially if one of them is a Macaroni, the last of which hatched at the Aquarium in 2015.
“I think potentially having chicks this year is exciting,” Gibson says. “It was nice to have an off-year last year, but you know, everybody loves penguin babies.”
The incubation time for Gentoo and Macaroni Penguin eggs ranges from 30 to 40 days, so if any of the eggs are viable, chicks could begin appearing in early June. In the meantime, penguin fans can keep an eye on the breeding season excitement and settle in for Chick Watch 2019 by viewing the Penguins’ Rock live webcam at tnaqua.org/animals-exhibits/penguins-rock-cam/