Connect with us
background

Marine Life & Conservation Blogs

Breeding at Blue Planet

Published

on

Breeding in the main tank at Blue Planet

Here at Blue Planet Aquarium we have many animals that live in our main tank, everything from our Sand Tigers all the way down to our Goliath Grouper. But there are a few animals in our main tank that breed on a more than Regular basis. In this article we are going to talk about three of them.

The first one is instantly recognisable as it is one of our signature animals, the Southern Atlantic Stingray. This species can grow up to nearly 5 feet across, with males being significantly smaller at around 2 feet across. Here at Blue Planet we have six adult stingrays, one male and five females with many of their offspring in a separate section of the tank. There are two main females who are breeding, and their names are “Big Bertha” and “Greedy” and we usually expect a litter from each between July and August, this can be anything between 2 – 6 pups on average per litter.

When we find pups in the tank we immediately drop whatever task we’re doing at the time and grab the ray nets (a specially designed flat net that can zip-up) in order to catch them. Every time we catch a pup we will keep going back into the tank until we’re satisfied that all pups have been captured. In the immediate days following the initial birth we will keep our eyes out for any other pups that may appear during the next few days.

Once captured the animals are placed in quarantine which is separate from the main exhibit. They’re kept here for around 6 weeks just so they get used to hand feeding and so that they can grow slightly before they go into the reef section, which is a smaller section of the main tank away from the larger sharks. The animals are kept until they’re large enough to either be moved to a different collection or go on display.

The next animal is probably the least noticed by our guests, it’s a small fish called a Sergeant-Major Damselfish. In the last year we’ve had an unbelievable number of clutches of such a vast amount that we’re finding new nests every day. The way in which they breed is quite fascinating.

Sergeant-Major Damselfish males lure females in with audio cues and “Signal Jumping” – this is where the male will swim erratically up and down, once the female has been attracted they will both change from their light blueish-green colour and turn almost completely dark blue until you can barely see their stripes, and males will develop a bright white patch on his cheek.

The female will lay up to 20,000 eggs and apparently there can be up to four females that add to any one clutch. Both males and females perform a kind of Ballet when laying eggs as they spin around with a head to tail position and then the female breaks away to deposit her eggs and as she finishes a clutch the male descends to fertilise them, this happens until all the eggs have been laid. The eggs are laid to the side of rocks and corals, usually on the roof of overhangs to maximise protection.

Males will guard their clutch ferociously and are now known by the dive team as the most aggressive animal in the tank; they’ve even been seen attacking the Sand Tigers (even though it doesn’t seem to bother them). Males will then spend the next 5-7 days of the gestation period constantly guarding and aerating them to stop fungus from settling on the eggs which would kill them, and just before hatching the eyes on the larvae turn a green colour.

Unfortunately due to the nature of the tank and larvae, we are still trying to figure out how we can harvest the fry to rear them in quarantine but unfortunately you need to be there at the moment they hatch and that usually happens at night. We have placed terracotta tiles in the tank to try and entice them to lay eggs on them so that they can be harvested. Even though we’re still trying to figure out how to harvest them it appears nature is best as we’ve actually seen young fish thriving in the main exhibit.

The final animal is the most cryptic of them all and this is of course  Bamboo Sharks. These Sharks spend most of their days sleeping in caves, holes and under overhangs; they’re shy until feeding time and then they’re our best friends. This Shark species lays eggs called “Egg cases/Mermaids Purses” and they lay their eggs around stems of coral or around rockwork. They do this by swimming very quickly over rockwork until the threads of the egg “hook” onto the rocks or coral and then they immediately swim quickly around in big circle causing the egg to slowly be pulled out and wrapped up against the piece of rockwork.

Now this is where the egg would stay if we didn’t find it, but once we find an egg we check them by “candling the egg” which is simply holding up to the light or shining a torch through it; if we see a yolk then it’s a viable egg. There are times we do this and see a shark pup still developing inside which is always a true joy to see. Once we’ve checked the egg is viable, we remove it and place it in our Shark hatchery to develop. The gestation period is usually around 4-5 months, but we check the progress by candling them just to monitor how they’re doing. When they hatch, they have very striking black and white stripes which are used to mimic White-Banded Sea Snakes, as these snakes in their native Indian Ocean habitat would be avoided by most predators (Zebra Sharks also use this form of mimicry). The pups stay in the hatchery until they’re around 10-12 inches long and are trained to feed from your hands and then we move them to another collection.

So, there you have it: Three amazing animals that breed in just our main tank exhibit alone. We do have many other breeding projects here at Blue Planet Aquarium which I’ll be covering in future blog posts.

For more information please visit the Blue Planet Aquarium website by clicking here.


Follow Donovan on Instagram at www.instagram.com/donovans_reefs

Donovan is a Divemaster who currently works as a Shark Diver at Blue Planet Aquarium based in Ellesmere Port. Donovan’s passion lies with Elasmobranch’s (Sharks & Rays) and this passion has led him to work in South Africa with White Sharks for a short period. He also believes that education through exposure is the best way to re-educate people about Sharks. Follow Donovan at www.instagram.com/donovans_reefs

Marine Life & Conservation Blogs

Creature Feature: Undulate Ray

Published

on

In this series, the Shark Trust will be sharing amazing facts about different species of sharks and what you can do to help protect them.

This month we’re looking at the Undulate Ray. Easily identified by its beautiful, ornate pattern, the Undulate Ray gets its name from the undulating patterns of lines and spots on its dorsal side.

This skate is usually found on sandy or muddy sea floors, down to about 200 m deep, although it is more commonly found shallower. They can grow up to 90 cm total length. Depending on the size of the individual, their diet can range from shrimps to crabs.

Although sometimes called the Undulate Ray, this is actually a species of skate, meaning that, as all true skates do, they lay eggs. The eggs are contained in keratin eggcases – the same material that our hair and nails are made up of! These eggcases are also commonly called mermaid’s purses and can be found washed up on beaches all around the UK. If you find one, be sure to take a picture and upload your find to the Great Eggcase Hunt – the Shark Trust’s flagship citizen science project.

It is worth noting that on the south coasts, these eggcases can be confused with those of the Spotted Ray, especially as they look very similar and the ranges overlap, so we sometimes informally refer to them as ‘Spundulates’.

Scientific Name: Raja undulata

Family: Rajidae

Maximum Size: 90cm (total length)

Diet: shrimps and crabs

Distribution: found around the eastern Atlantic and in the Mediterranean Sea.

Habitat: shelf waters down to 200m deep.

Conservation Status : As a commercially exploited species, the Undulate Ray is a recovering species in some areas. The good thing is that they have some of the most comprehensive management measures of almost any elasmobranch species, with both minimum and maximum landing sizes as well as a closed season. Additionally, targeting is entirely prohibited in some areas. They are also often caught as bycatch in various fisheries – in some areas they can be landed whilst in others they must be discarded.

IUCN Red List Status: Endangered

For more great shark information and conservation visit the Shark Trust Website


Image Credits: Banner – Sheila Openshaw; Illustration – Marc Dando

Continue Reading

Blogs

Guarding Against Coral Invaders

Published

on

coral

Protecting (Dutch) Caribbean Reefs from Unomia stolonifera

Recent reports highlight the concerning spread of the invasive soft coral, Unomia stolonifera, currently devastating Venezuela’s marine ecosystems and detected in Cuba. With the potential threat of its expansion to the (Dutch) Caribbean islands, urgent action and awareness are essential to safeguard marine biodiversity and local economies from possible catastrophic consequences.

Invasive species are animals or plants from another region of the world that don’t belong in their new environment. These species can have major ecological effects by decimating native flora or fauna. They can also cause large economic losses and impact human health. Invasive species also pose a significant threat to marine ecosystems worldwide, including the Dutch Caribbean. Among these invaders is the octocoral species Unomia stolonifera or “Pulsing Xenia”, originally from the Indo-Pacific. With its rapid growth and lack of natural predators, this species can outcompete native species and disrupt fragile marine habitats such as seagrass beds and coral reefs.

Background

The invasive soft coral U. stolonifera was first identified in 2014, off the coast of Venezuela. It is believed to have been introduced via the illegal aquarium trade.  Since this species can reproduce sexually and asexually (or fragment), even small pieces can regenerate to spread.  Once introduced it quickly took over shallow reefs and hard substrate at depths of 0-50 meters, outcompeting local corals and seagrass for space.  Follow on surveys found that this coral species exhibited average percentage cover as high as 80%, vastly outcompeting native corals. In highly colonized areas, fish are disappearing due to loss of habitats.

In 2022, during a survey conducted in Cuba by the University of Havana, an unknown octocoral was discovered which was later identified as the invasive Unomia stolonifera. It is suspected that the coral larvae arrived in ballast water from fossil fuel ships originating from Venezuela, as nearby sites adjacent to Venezuelan ports have been heavily affected by the invasion.

How to help

Prevention through continuous monitoring, particularly in high-risk areas such as marine harbors and oil facilities, is paramount. Early detection plays a pivotal role in mitigating the threat posed by Unomia stolonifera.

The public’s involvement and awareness are also vital. Local communities, recreational divers, tourists, and all stakeholders are urged to participate in early detection efforts by reporting sightings (photo, location and date) of this invasive coral to their respective Protected Area Management Organization (PMO’s)- the Fundacion Parke Nacional Aruba (FPNA)STINAPA BonaireCARMABI Curaçao Saba Conservation Foundation (SCF)Nature Foundation St. Maarten (NFSXM) and St. Eustatius National Parks (STENAPA). If an invaded area is confirmed, follow the recommendations by the local PMO’s.

Keys to Success

Despite the challenges, early detection is key to mitigating the threat posed by Unomia stolonifera. With continued vigilance, research, and community engagement, there is hope for containing this potential issue before it becomes a major threat.

About the DCNA

The Dutch Caribbean Nature Alliance (DCNA) supports (science) communication and outreach in the Dutch Caribbean region by making nature related (scientific) information more widely available through amongst others the Dutch Caribbean Biodiversity Database, DCNA’s news platform BioNews and through the press. This article contains the results from several scientific studies but the studies themselves are not DCNA studies. No rights can be derived from the content. DCNA is not liable for the content and the in(direct) impacts resulting from publishing this article.

Continue Reading

E-Newsletter Sign up!

Experience the Red Sea in May with Bella Eriny Liveaboard! As the weather warms up, there’s no better time to dive into the crystal clear waters of the Red Sea. Join us on Bella Eriny, your premier choice for Red Sea liveaboards, this May for an unforgettable underwater adventure. Explore vibrant marine life and stunning coral reefs Enjoy comfortable accommodation in our spacious cabins Savor delicious meals prepared by our onboard chef Benefit from the expertise of our professional dive guides Visit our website for more information and to secure your spot: www.scubatravel.com/BellaEriny or call 01483 411590 More Less

Instagram Feed

Popular