Madeira rockfish


The Madeira rockfish is a species of scorpionfish in the genus Scorpaena, found in the coastal waters of the eastern Atlantic Ocean and the Mediterranean Sea. This species reaches a length of around SL. The species was described by Achille Valenciennes in 1833 after a specimen from Madeira. Although S. maderensis is well represented in the areas that it is found, many key aspects of its biology are still unknown.

Description

S. maderensis grow between 4.8 cm and 13.1 cm and weigh between 1.7 and 48.1 g, with males being larger in both categories. Females achieve their maximum size faster and live longer than males. The maximum recorded length for males and females is around 15 cm and 9.0 cm respectively. S. maderensisexhibits many similar characteristics to other Scorpaena, such as spiny fins and a reddish-brown splotched color but there is a lack of sufficient specific information. However, one well-known similar characteristic is the presence venomous spines due to an anterolateral glandular grove containing venom. Venom from Scorpaenidae causes many health issues and can be fatal if not treated.

Habitat

S. maderensis inhabits the littoral rocky coastal waters of the northwestern coast of Africa, the Mediterranean Sea and islands in the eastern Atlantic. S. maderensis is considered crypotbenthic, which describes fish that are benthic and cryptic. S. maderensis lives in the cracks and crevices of the rocky bottom, where it is able to hunt for prey and hide from predators. Gauging the abundance of S. maderensisthroughout the entire Mediterranean Sea is difficult due to lack of data; however extensive research has been done in the off the coast of Sicily, and S. maderensis was found to be the dominant species in that area. There seems to be conflict on the preferred depth of S. maderensis as some research says 20 to 40m depth, while some finds it mostly above 7m and dropping off at 13m. This discrepancy is due to lack of data collected on S. maderensis, making it difficult to pinpoint a concrete depth range.

Feeding Habits

S. maderensis feeds primarily on benthic and epibenthic crustaceans, while sometimes consuming algae, gastropods, polychaetes and other fishes. Many of the organisms that S. maderensis consumes are considered rare or unimportant, showing that S. maderensis feeds on a wide variety of species along the trophic spectrum. S. maderensis also has a “strong individual feeding specialization," meaning that consumption varies from individual to individual because S. maderensis are opportunistic feeders, preying on whichever organisms happen to be around them. Feeding of S. maderensis follows a seasonal trend, with higher intensity in the winter months and lower intensity in the summer months.

Relationship to Humans

S. maderensis is a target species of the artisanal fisheries along the coasts but is in no danger of overfishing or extinction. While S. maderensis may not be in any danger, the artisanal fisheries may have a negative affect on its reproduction capabilities. Due to their venomous spines they can injure divers, fisherman and the casual swimmer if correct precautions are not taken.
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