The Odyssey Bracelet

Per our partners at the FIU Marine Mammal Ecology Lab, dolphins are tracked to better understand their movements and predict how environmental changes and human activities affect their populations! The specific goal of this project, being conducted in collaboration with their partner organization, the Sarasota Dolphin Research Program, is to learn about the health and movements of dolphins residing over the offshore waters of the West Florida Shelf. The primary dolphin species inhabiting this more than 100-mile-wide continental shelf are bottlenose and Atlantic spotted. Prior to this project, little was known about their ranging patterns or their health in these offshore waters.

To learn more about the work our partner is doing, visit their site directly at marineconservationecologylab.com.

The dolphins are tagged with satellite-linked transmitters that report their locations and other data every other day. The very small and hydrodynamic tag is attached by means of a small pin through the trailing edge of the dorsal fin, and comes off the fin after the end of the battery life of the tag.

Per our partners at the FIU Marine Mammal Ecology Lab: "No, otherwise we would not want to do it, nor would we be allowed to do it, as these are federally protected species. The research is being conducted under a Marine Mammal Protection Act permit issued by NOAA-NMFS to the Sarasota Dolphin Research Program, and through Institutional Animal Care and Use Committee approvals. The tag design has been tested on hundreds of dolphins over more than 10 years and has no effects on the movements and behavior of the tagged dolphins." 

Dolphins are primarily carnivorous and their diet largely consists of various species of fish and squid. The specific type of prey can vary greatly depending on the dolphin's geographic location, species, and local ecosystem. For example, bottlenose dolphins typically consume fish like herring, cod, and mackerel, as well as cuttlefish and squid. As dolphins are integral parts of the marine ecosystem and their dietary habits provide valuable insights into the health of oceans, dolphin tracking and their conservation is crucial. 

Dolphins exhibit a wide lifespan range based on their species. Common species like bottlenose dolphins can live for about 40 to 50 years, though some individuals have been known to live into their 60s! Factors like predation, disease, pollution, and human-related threats such as fishing net entanglements or marine habitat destruction all affect dolphin lifespans.

Dolphins form groups that usually consist of anywhere between 2 and 5,000 individuals! Group size varies considerably from one species to another, and can be influenced by food availability or the risk of predation (from large sharks and killer whales). Coastal dolphin species such as bottlenose dolphins form small groups that change composition frequently, in a manner referred to as “fission-fusion.” They can be seen alone on occasion or they can sometimes be seen in groups of up to 20–30 individuals, particularly when they socialize! In the open ocean, spinner or common dolphins can form groups of thousands of individuals, which helps them to remain vigilant towards predators, or find widely distributed food.

Several species of dolphins are classified as endangered due to a variety of human-related factors. Overfishing has resulted in a significant decrease in the amount of prey available, threatening their survival. Additionally, dolphins often get caught in fishing gear, leading to injury or death. Pollution, including plastic waste and harmful chemicals, degrade their habitats and can directly harm dolphins through ingestion or exposure. Climate change also poses an increasingly urgent threat by altering habitats and food sources, while habitat degradation from coastal development and noise pollution from maritime activities disturb dolphin behaviors and communication.

Several dolphin species are currently listed as endangered or critically endangered according to the International Union for Conservation of Nature (IUCN), including the bottlenose dolphin, pantropical spotted dolphin, and Indian Ocean humpback dolphin. This list includes critically endangered species, with populations numbering fewer than 100 individuals. Unfortunately, the Yangtze River dolphin is believed to have gone extinct in the early 21st century. Other species facing serious threats include the Atlantic humpbacked dolphin and the Indus and Ganges River dolphins. Each of these species face numerous threats, including habitat loss, bycatch in fishing gear, pollution, and a decrease in food availability due to overfishing.