Fish Lab and Marine Life
Landaa Giraavaru’s Fish Lab breeds ornamental fish to promote marine conservation and education among guests and local school children, with the future aim of establishing fish breeding on neighbouring local islands as an alternative source of livelihood.
The aquarium fishery in the Maldives is regulated to safeguard tourism. While this goes some way to protect the reefs, it also limits growth in the lucrative ornamental sector – estimated to have an annual worldwide trade value of USD 220-300 million. Although some ornamental marine species have been successfully reared in farms or labs, it is important to note that the majority (90%) of species available to international aquarists and hobbyists have been collected from the wild. Captive cultivation techniques enable the production of hardy and disease-free fish, reducing pressures on the reef and eliminating the dangerous impacts associated with other forms of collection, such as the use of chemicals or breaking the corals. It can also provide a valuable alternative and sustainable source of income to local communities.
See also: Our Zooplankton Monitoring Project
Clownfish & Damselfish
Our most recognisable residents are clownfish, a well-known family of fish found in all tropical waters, made famous by the movie ‘Finding Nemo’. We also breed a close relative of the clownfish called the damselfish, which is in high demand for the aquarium industry. We breed two common local clownfish species in the Maldives:
- the Maldivian anemonefish (Amphipion nigripes) with its single white stripe;
- the Clark’s anemonefish (Amphiprion clarkii) with three white stripes.
Breeding females lay between 200 to 1500 eggs per clutch, which the parents guard and care for over six to seven days (clownfish) or three to four days (damselfish). During this time, we also monitor egg development and the health of the clutch, so we can estimate when the larvae will hatch. After hatching, we collect the larvae and place them in a separate tank, where we closely monitor their growth and feed them a suitable diet. If possible, we try to move the egg clutch just prior to hatching, to reduce stress.
In nature, only a tiny proportion of fish larvae survive to adulthood (1 in 150,000). In the Lab, we can ensure greater survival rates by eliminating predation and increasing the larvae’s food capture potential. Our live food lab produces and grows both rotifers and Artemia, to ensure that our larvae and baby fish have a constant supply of suitable fresh food.
- For the first 5 days, the larvae consume approximately 350-600 rotifers (plankton) per day.
- From day 6, larvae are given Artemia (brine shrimp).
- By day 10 to 15, larvae start metamorphosis to become fish, developing the stripes and colouration that characterise the species.
Our approach is simple: “A happy fish is a healthy fish”.
To maintain this requires dedication for each of the different ornamental fish species we are trying to breed.
To maintain this requires dedication for each of the different ornamental fish species we are trying to breed
We have also been attempting to breed the common seahorse (Hippocampus kuda), with the first juveniles successfully produced back in 2012. Juvenile seahorses are hungry little animals that devour a lot of rotifers and Artemia (just like the clownfish larvae). They are not easy to rear as they are very fragile, and sensitive to parasites, and can suffer from a deadly ailment called ‘air bubble syndrome’.
The purpose of breeding seahorses in our Fish Lab is to further demonstrate an alternative to harvesting them from the wild. There is so little data available on seahorse species that we stand at risk of losing them globally, purely through not knowing enough about them. These reasons – compounded by the global deterioration of seahorses’ coral reef and sea grass habitats – make us even more passionate about breeding and rearing them here in our Fish Lab. Through our research and refining of breeding and raising protocols, we gain valuable information about the care, reproduction, and lives of these animals.
We invite you behind the scenes to watch the refurbishment process of our large (4000L) marine aquarium at Landaa Giraavaru’s Marine Discovery Centre, back in 2017 (time flies!) Two months in the making, and all of Aku and Carla’s hard work is paying off ! Enjoy our photo slideshow of the construction process, and meet all the inhabitants in our DIARY feature on corals, invertebrates and fish.
Most of the research surrounding shrimp aquaculture concerns the commercial production for human consumption.
We are attempting to breed different species of ornamental shrimp that are popular for hobbyists and aquaria alike.
The Coral Banded Shrimp (Stenopus hispidus) and the Sexy Shrimp (Thor amboinensis) are in particular high demand.
Currently, most attempts to breed shrimp fail at the larval stage as they are very delicate, so our research could impact the early-stage lifecycle care of these species.
Our Shrimp Fact Cards
Dancing Shrimp (Thor amboinensis)
The smallest of our shrimp species in the Fish Lab, growing to only 20mm maximum, they are also the most sociable, preferring to live in large groups. They are the only species in the Lab to have a symbiotic relationship with anemones and corals.
Despite their small size, Dancing Shrimp can be easy to spot as they are a bright red/orange in colour, with large white markings along the body and tail. Males have an unbroken stripe across the tail, whereas in females it is broken into three large spots. Females are also much larger than the males as they are protandrous hermaphrodites, transitioning from male to female based on size.
Dancing Shrimp have a very short abdomen and an unusual raised tail, which they hold above their head and wiggle back and forth (this is where the species gets its common name). It is not clear why they ‘dance’ like this, perhaps for communication. Eggs are held under the tail, and upon hatching the 2mm larvae are light brown and the same thickness along the body.
Boxer Shrimp (Stenopus hispidus)
The largest of our Fish Lab shrimp species, growing to 75mm in length. Preferring to be in pairs, the Boxer Shrimp is highly territorial, and can become aggressive to other shrimps (except their mated partner). They have very distinctive colouring, like a candy cane, with red and white stripes all over the body including on the pincer claws. They also have long antennae which extend well past the body. The females are larger than the males, and typically wider in the abdomen to allow for eggs to be stored underneath.
Eggs are a bright blue/green when immature, fading to white as they develop. Shortly before hatching, black spots become visible within the eggs. The larvae are large (3-4mm) and begin to show red and white banding at an early age, as well as the spines used for protection in the adults.
Marbled Shrimp (Saron marmoratus)
Growing to 50-75mm, they are one of the more unusual looking species. The body is covered in a mix of spots, blotches and stripes of various colours (grey, yellow, red, brown and even green). The legs are striped in either blue/white or red/white, and the eyes are large and dominant on the head.
The body of the Marbled Shrimp is covered in tufts of cilia on both the back and underside. Females have large tufts of these cilia on the front legs (looking almost like a toothbrush!) while in males this is absent or reduced. They also have the ability to camouflage, and have been recorded changing colour dramatically between day and night.
The larvae are large at 3mm, with a wide carapace, almost 2x wider than the other species.
Camel Shrimp (Rhynchocinetes durbanensis)
This species is commonly mixed up with the Peppermint Shrimp (Lysmata wurdemanni) as they have similar colouring and size (50 mm). The shrimp is red, with a cream/white striping and spots in a geometric pattern, with a long white stripe around the mid-section which has a hump like a camel’s back. They have a long rostrum beak, which is mobile and swings up and down. This is why they are also sometimes called Hinge-beak Shrimp as well as Camel Shrimp. Males and females are similar sizes, but the females tend to be smaller with smaller pincers.
Eggs are dark grey and easily visible under the abdomen and through the side of the body. The larvae are a similar shape to the larvae of the S. marmoratus but smaller (only 1.5-2mm), with a much narrower carapace, though still wider than both T.amboinensis and S. hispidus.
Skunk Cleaner Shrimp (Lysmata amboinensis)
This species is usually associated with cleaning stations and is easily seen with on the reef due to their long white antennae that extend past the body.
They have a yellow underbelly, and bright red back with a long white stripe that runs from the head to the tail, and are relatively large for a cleaner species at 2 inches .
This species is hermaphroditic, producing both eggs and sperm at the same time, making pairing easy; they can store reproductive materials until required. The eggs are green when first produced, and fade to clear as they develop (similar to S. hispidus.)