3-Trees, 9-mile, and 2-mile reefs), but giant manta rays are rare, as they spend most of their time in deeper waters. Reef manta rays are encountered regularly during scuba dives in other parts of the archipelago (e.g. Our surface-sighting records show that manta rays predominantly occur in two areas: south of the Bazaruto Archipelago on the east side of Magarruque Island and near the Canyon (see below), as well as off the north side of Bazaruto Island. It is during this period that we see more manta rays in the Bazaruto Archipelago and surroundings. After the arrival of phytoplankton, zooplankton typically follows as zooplankton feeds on phytoplankton. The colder water contains high quantities of nutrients, which combined with sunlight warms up and may trigger phytoplankton blooms. Strong and sudden Mozambique Channel wind reversals trigger upwelling of colder water (water being pushed up from the deeper ocean to shallower water columns) resulting in higher density of plankton: the primary food source of both reef manta rays (M. Manta ray season in the Mozambique Channel starts around February, when seawater temperatures drop from the peaks of the summer, and large amounts of plankton are trapped in fronts and eddies as well as after upwelling events. Being pelagic, giant manta rays travel further than reef manta rays, as they embark on ocean crossings, covering the Pacific, Atlantic and Indian Ocean, where the reef manta ray is only found in the Indian ocean and part of the Pacific Ocean and usually keeps to smaller, coastal areas throughout their lives, for example the Bazaruto Archipelago. Reef manta rays are found globally in (sub)tropical waters, whereas oceanic manta rays are found in both (sub)tropical and temperature ocean waters. Other differences between the manta ray species are the fact that there are no spots in between the gills of giant manta rays and the dark edges at the end of the bottom of their fins. The two species look very similar, however, reef manta rays are typically 3 to 3.5 meter in disc width ( the largest reef manta rays have been found in Mozambique, sizing up to 5m in disc width), while giant oceanic manta rays can impressively reach up to 9 meters in size. Though, only in 2008 scientists discovered that there are two species of manta ray, not one. Research has proven that manta rays can recognise themselves in the mirror, which is considered a high cognitive function. Manta rays have sparked the interest of scientists globally for decades, for one because the species have the biggest brain-to-size ratio of any fish, indicating high intelligence.
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