The Shedd Aquarium in Chicago has successfully raised a warty frogfish, named Domino, from an egg to a juvenile. This marks the first known instance of a warty frogfish being reared in captivity.
Warty frogfish are ambush predators found in the Indo-Pacific region, known for their yellow color, wart-like bumps, and use of a modified dorsal fin as a lure for prey.
Rearing Process and Challenges
Last year, a female warty frogfish at the Shedd Aquarium released tens of thousands of translucent eggs, which were subsequently fertilized by a male. Aquarists quickly retrieved the egg raft and began efforts to raise them behind the scenes. Jenny Richards, a senior aquarist, noted the rare opportunity and the challenges involved.
Marine fish larvae are fragile and require specific conditions to mimic their open ocean environment, including appropriate lighting, flow, temperature, and diet. The team at Shedd Aquarium, drawing on previous experience with other species, focused on 500 larvae. They provided tiny crustaceans called copepods for food, which were crucial once the larvae's yolk reserves depleted.
Over approximately 90 days, the larvae underwent significant anatomical changes. During this process, the number of surviving larvae decreased, a natural occurrence mirroring wild conditions, until only three remained.
Continuous adjustments were made to light levels and water flow based on the larvae's behavior, leading to one larva successfully transitioning into a pea-sized juvenile, Domino.
Broader Implications
Although warty frogfish are not currently endangered, they face threats from climate change, habitat destruction, and collection by traders. The successful rearing of Domino is considered significant for future marine conservation efforts.
Nicole Rhody, program manager at Mote Marine Laboratory, highlighted the difficulty of recreating natural conditions in captivity and praised the Shedd team's rapid success.
This achievement provides valuable insights that could assist in raising other marine species in captivity, which is becoming increasingly important due to changing ocean conditions. Aquarists at Shedd Aquarium hope Domino will eventually be exhibited to the public.