Rising up as a shark may be powerful. You not solely have to fret about being eaten whereas nonetheless inside your mother’s womb, however while you lastly come out, there isn’t a parental care! From the second you hit the water, you’re by yourself… and normally fairly small! So, whereas Momma Shark may not maintain her infants (known as ‘pups’) in a standard sense than we’re used to, she does attempt to give them their greatest preventing likelihood by giving start in a nursery.
Many species of tropical sharks use semi-enclosed our bodies of shallow water equivalent to bays and estuaries as a nursery. Mangrove environments and seagrass meadows are the popular habitat for some whereas different coastal sharks are tailored to make use of open techniques equivalent to bays, river deltas, shallow seashores, and different coastal fringe habitats.
Information concerning the traits of shark nursery areas is usually primarily based on coastal species attributable to it being simpler to look at them than their pelagic counterparts (and a few pelagic sharks don’t even use nurseries). In heat temperate to tropical areas, the nurseries are sometimes extremely productive, semi-enclosed habitats, usually surrounded by mangroves, sandbars, or reefs – constructions that make it powerful for bigger sharks to infiltrate and prey upon the rising pups. The time younger sharks spend in nurseries is determined by each biotic and abiotic elements that aren’t totally understood.
The lemon shark (Negaprion brevirostris) is considered one of many species within the Caribbean that use a nursery, and far of what’s recognized about their replica and nursery areas is from long-term research within the Bahamas over a number of a long time. They had been first described by Cuban ichthyologist Felipe Poey greater than 150 years in the past as a species present in Cuban waters however are have a bigger tropical distribution within the Atlantic Ocean, Caribbean, and Japanese Pacific. They like heat, shallow waters with sandy bottoms and are recognized to make use of coastal habitats (e.g. mangroves) to present start and supply meals and safety from predators for the younger.
However the Bahamas is probably not the one lemon shark hotspot within the Caribbean Sea. On the southwestern coast of Cuba is La Salina Wildlife Refuge, overseen by the Empresa para la Conservación de la Ciénaga de Zapata (Zapata Swamp Conservation Enterprise). Right here, a discipline station stands that screens the native wildlife… together with small lemon sharks. Primarily based on these informal observations, a group led by scientist Alexei Ruiz-Abierno of the Centro de Investigaciones Marinas (Universidad de La Habana) carried out an exploratory survey to see how why how these sharks had been utilizing the protected habitat. “The research was aware of analysis wants specified within the Nationwide Plan of Motion (NPOA) for sharks in Cuba, with a aim of informing each fisheries administration and conservation initiatives for sharks in Cuban waters,” said the authors.
La Salina Wildlife Refuge is a semi-enclosed refuge, protected by thick mangrove roots to bar any massive animals from coming inside. It’s always nourished by the a number of openings it has into the Gulf of Cazones and the Caribbean Sea, a simple exit for the younger sharks once they really feel they’ve outgrown the realm. Human exercise within the space is virtually nonexistent, with fishing contained in the refuge is prohibited (apart from the catch-and-release leisure fly fishing). To study extra concerning the sharks calling this space residence, the group needed to do extra than simply casually observe them… they needed to seize them. Completely different hook-and-line strategies had been used, and the captured sharks had been then measured, sexed, weighed, tagged, and launched. The researchers had been even in a position to determine how outdated the sharks had been by whether or not or not that they had an open umbilical scar (making them neonates) or had been juveniles with closed umbilical scars.
Two species of sharks had been caught, lemon sharks (101) and nurse sharks, Ginglymostoma cirratum (5). The 5 nurse sharks had been discovered solely in deeper waters, near the openings that join the La Salina system to the deeper water of the Gulf of Cazones. However, the lemon sharks had been captured principally within the shallow waters of the coastal lagoons and the margins of mangrove keys, exhibiting no evident patterns of dimension or intercourse distribution. “We captured just one lemon shark longer than three toes (1 meter), within the southeast a part of the realm near a gap to the Gulf,” the authors stated. “The seize of this particular person was per native fishing information data that larger sharks are noticed within the deepest areas near the entrances or channels on the southern border.”
“Our research was primarily based on a particularly small pattern dimension, so extra analysis is required on juvenile lemon shark progress in La Salina,” the authors confused about their findings. “The habitat for juvenile lemon sharks in La Salina is per the standard description of this species’ nursery areas, which embrace shallow and semi-enclosed marine/estuarine techniques which have been extensively documented primarily within the Bahamas and areas of the Southwest Atlantic.”
Though Cuba doesn’t have any particular marine protected areas (MPAs) designated for elasmobranchs, the Cuban NPOA-Sharks is within the means of recognizing and finding out important habitats for sharks in Cuban waters. “With robust enforcement of refuge rules, troublesome entry (being surrounded by a swamp), and isolation from human inhabitants facilities, the lemon sharks of La Salina signify youth phases that doubtless are unaltered by important human impacts,” the authors stated.