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Iberian Orca Attacks
Beginning in 2020, a subpopulation of orcas (''Orcinus orca'') began ramming boats and attacking their rudders in waters off the Iberian Peninsula. The behaviour has generally been directed towards slow-moving, medium-sized sailboats in the Strait of Gibraltar and off the Portuguese, Moroccan and Galician coasts. The novel behaviour is thought to have spread between different pods, with over 500 reported interactions from 2020 to 2023 attributed to fifteen different individual orcas (the exact number is still debated between certain scientists). Background The Iberian orca subpopulation lives in the coastal waters of the Iberian Peninsula and is genetically distinct from other orca populations in the Northeast Atlantic. The orcas follow the seasonal migration of Atlantic bluefin tuna (''Thunnus thynnus''), their primary food source, gathering in the early spring in the Strait of Gibraltar. Through the summer, they remain in the Strait before travelling north along the coast of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orca
The orca (''Orcinus orca''), or killer whale, is a toothed whale and the largest member of the oceanic dolphin family. The only extant species in the genus '' Orcinus'', it is recognizable by its black-and-white-patterned body. A cosmopolitan species, it inhabits a wide range of marine environments, from Arctic to Antarctic regions to tropical seas. Orcas are apex predators with a diverse diet. Individual populations often specialize in particular types of prey, including fish, sharks, rays, and marine mammals such as seals, dolphins, and whales. They are highly social, with some populations forming stable matrilineal family groups (pods). Their sophisticated hunting techniques and vocal behaviors, often unique to specific groups and passed down from generation to generation, are considered to be manifestations of animal culture. The International Union for Conservation of Nature (IUCN) lists the orca's conservation status as data deficient as multiple orca types ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Knot (unit)
The knot () is a unit of speed equal to one nautical mile per hour, exactly (approximately or ). The ISO standard symbol for the knot is kn. The same symbol is preferred by the Institute of Electrical and Electronics Engineers ( IEEE), while kt is also common, especially in aviation, where it is the form recommended by the International Civil Aviation Organization ( ICAO). The knot is a non- SI unit. The knot is used in meteorology, and in maritime and air navigation. A vessel travelling at 1 knot along a meridian travels approximately one minute of geographic latitude in one hour. Definitions ;1 international knot = :1 nautical mile per hour (by definition), : (exactly), : (approximately), : (approximately), : (approximately) : (approximately). The length of the internationally agreed nautical mile is . The US adopted the international definition in 1954, having previously used the US nautical mile (). The UK adopted the international nautical mile defi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satellite Tag
Pop-up satellite archival tags (PSATs) are used to track movements of (usually large, migratory) Marine (ocean), marine animals. A PSAT (also commonly referred to as a PAT tag) is an archival tag (or data logger) that is equipped with a means to transmit the collected data via the Argos_(satellite_system), Argos satellite system. Though the data are physically stored on the tag, its major advantage is that it does not have to be physically retrieved like an archival tag for the data to be available making it a viable, fishery independent tool for animal behavior and migration studies. They have been used to track movements of ocean sunfish, marlin, blue sharks, bluefin tuna, swordfish and sea turtles to name a few species. Location, depth, temperature, oxygen levels, and body movement data are used to answer questions about migratory patterns, seasonal feeding movements, daily habits, and survival after catch and release, for examples. A satellite tag is generally constructed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
