Named for the silky appearance of its skin, silky sharks are long & slender, with a relatively short first dorsal fin, a second dorsal fin with a long free tip, and elongated pectoral fins. These pelagic sharks are found worldwide in warm & temperate waters and were once one of the most abundant sharks.
Unfortunately, these sharks are often caught as bycatch in the tuna industry and are targeted for their fins, resulting in a decline in their numbers. Silky sharks are very social sharks and tend to travel in larger groups, or schools of sharks.
At-A-Glance
Scientific Name – Carcharhinus falciformis
Size – 8.2 ft/2.5 m. The largest documented silky shark was a female who was 11 ft/3.5 m long and weighed 763 lb/346 kg!
Habitat – Tropical, warm waters. It is most common to see them hanging out in waters more shallow than 656 ft/200 m near continental and insular shelves. Younger sharks are usually found closer to the coast while adults can be observed in the open ocean.
Diet: Bony fishes, cephalopods (squid, octopus, and cuttlefish), and, sometimes, crustaceans (crabs, lobster, shrimp, and krill). They also love tuna!
Reproduction – Silky sharks breed every two years after they mature, which takes 5 to 15 years. When in tropical waters, they will breed year round with no preference for a particular season. However, silky sharks found in the Gulf of Mexico generally only breed during the summer months of June, July, and August. They are viviparous, meaning they give birth to live young and use a placenta to deliver nutrients while they are in the womb, like humans. There are usually between 2-18 pups in one litter and it takes 9 to 12 months for the gestation period to complete.
Lifespan – Around 22 years.
IUCN Listing – Near threatened; however, populations in the Eastern Central and Southeast Pacific and Northwest and Western Central Atlantic are categorized as being vulnerable.
Protection – The silky shark has been listed on Appendix ll of CITES, which restricts international trade of these sharks. Additionally, the Western and Central Pacific Fisheries Commission has prohibited fisheries from retention, transshipment, storage, or landing of these sharks caught inside the convention region. Efforts have also been made to minimize incidence of bycatch of this species which occurs when species are accidentally caught by fisheries targeting a different species.
Bet You Didn’t Know…
- Silky sharks are extremely social – they’ve been observed schooling in hundreds!
- They get their name from their skin! On the surface of their skin they have very tightly packed dermal denticles, making their skin appear and feel very smooth.
- They have also been called net-eater sharks because they have been known to attack tuna seine nets in search of a tasty meal.
- Silky sharks are one of the most sought after sharks for the fin trade; from 1995 to 2020, their population declined by 63 percent due to finning practices.
Ready To Dive In?
- Umkomaas, South Africa; ideal time is from April to June.
- Rangiroa, Polynesia; ideal time is from July to November.
- Protea Banks, South Africa; ideal for diving year round!
- Andros Island, Bahamas; good spot for diving throughout the year.
- Cabo San Lucas, Mexico; this is a great spot for diving all year.
- Socorro Island, Mexico: schooling Silky Sharks April/May but great diving year round.
Science In The Spotlight
Dorsal fins are extremely important for sharks’ ability to move throughout the water by stabilizing their bodies and preventing them from rolling over. Many marine animals sustain injuries to their dorsal fins throughout their lifetimes, which impacts their ability to move and remain upright. However, it has been found that some silky sharks have the ability to regrow their dorsal fin if it becomes injured.
Images for this month’s Monthly Chomp were provided by photographers diving off of the Solmar V Liveaboard in Socorro!
Hear more about it from one of their representatives below:
“Experience the thrill of encountering silky sharks on a diving adventure with the Solmar V in Socorro! Known for its crystal-clear waters and pelagic marine life, Socorro is a premier destination for divers. Silky sharks, renowned for their smooth skin and agile movements, frequent these waters, offering divers a rare opportunity to observe these magnificent creatures up close in their natural habitat. You might even get lucky and see a school of silkies usually during the months of April and May. Join us on the Solmar V for an unforgettable diving experience and create memories that will last a lifetime!”
To learn more visit Solmar V’s website.
Written by Greer Jessie, BS Undergraduate Student, University of Florida and Shark Angels Intern
Photos provided by Solmar V Liveaboard