User:Hallermb/Vampire squid

Illustration of the Vampire Squid with photophores used for bioluminescence

Habitat and adaptations: Fuka Reale

The vampire squid is an extreme example of a deep sea cephalopod, thought to reside at aphotic(lightless) depths in the mesopelagic zone, from 600 to 900 meters (2,000 to 3,000 ft). Within this region of the world's oceans is a discrete habitat known as the oxygen minimum zone (OMZ), ranging from 200 to 1500 meters. Within the zone, the saturation of oxygen is too low to support aerobic metabolism in most complex organisms. The vampire squid is the only cephalopod able to live its entire life cycle in the minimum zone, at oxygen saturations as low as 3%.

To cope with life in the suffocating depths, vampire squids have developed several adaptations: Of all deep-sea cephalopods, their mass-specific metabolic rate is the lowest. Their blue blood's hemocyanin binds and transports oxygen more efficiently than in other cephalopods, aided by gills with an especially large surface area. The animals have weak musculature, but maintain agility and buoyancy with little effort because of sophisticated statocysts (balancing organs akin to a human's inner ear)and ammonium-rich gelatinous tissues closely matching the density of the surrounding seawater. The statocytes consist of receptors that pick up the squid's position and movement in space. This adaptation is helpful for equilibrium orientation and spatial awareness and controls the squid's eye movments. The vampire squid's ability to thrive in OMZs also keeps it safe from apex predators that require a large amount of oxygen to live.

...At the shallower end of the Vampire Squid's vertical range, the view from below is like the sky at twilight: The highly sensitive eyes of deepwater dwellers are able to distinguish the silhouettes of other animals moving overhead. To combat this, the vampire squid generates its own bluish light (bioluminescence) in a strategy called counterillumination: The light diffuses the animal's silhouette, effectively "cloaking" its presence from the watchful eyes below. Its own large eyes detect even the faintest of gleams. A pair of photoreceptors are located on top of its head, perhaps alerting the animal to movements above. Bioluminescence is an important adaptation for predator avoidance. Vampire squids have arm tip light organs that produce luciferin and luciferase, allowing them to glow in the darkness of the deep sea. The squids can use these organs as a sacrificial tag by biting or breaking off its arm to divert predators. These glowing arm organs can also be used as a lure to attract smaller prey such as copepods.

Development and Reproduction: Claudio Gomes

If hypotheses may be drawn from knowledge of other deep-sea cephalopods, the vampire squid likely reproduces slowly by way of a small number of large eggs. Ovulation is irregular and there is minimal energy devotion into the development of the gonad. Growth is slow, as nutrients are not abundant at depths frequented by the animals. The vastness of their habitat and its sparse population make procreative encounters a fortuitous event. The female may store a male's hydraulically implanted spermatophore (a tapered, cylindrical satchel of sperm) for long periods before she is ready to fertilize her eggs.

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Their reproductive strategy appears to be of the iteroparous type, which is an exception amongst the otherwise semelparous Coleoidea. During their life, Coleidea cephalopods are thought to go through only one reproductive cycle whereas vampire squid have sown evidence of multiple reproductive cycle. After releasing their eggs, new batches of eggs are formed after the female vampire squid returns to a resting. Such process may repeat up to and sometimes more than twenty times. It has been hypothesized that the iteroparous lifestyle of the vampire squid has evolved with the squid's relaxed lifestyle. With iteroparity often seen in organisms with high adult survival rates, such as the vampire squid, many low-cost reproductive cycles would be expected for the species. Thus, in iteroparous fishes the resting phase, also called gonadal resting phase, the adults have no growing oocytes or ripe eggs in the ovary.

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Summary (at top of Article)[edit]: Marisa Haller

The vampire squid (Vampyroteuthis infernalis, lit. "vampire squid from Hell") is a small cephalopod found throughout temperate and tropical oceans in extreme deep sea conditions. The vampire squid uses its bioluminescent organs and its unique oxygen metabolism to thrive in the parts of the ocean with the lowest concentrations of oxygen. It has two long retractile filaments,

located between the first two pairs of arms on its dorsal side, which distinguish it from both octopuses and squids, and places it in its own order, Vampyromorphida, although its closest relatives are octopods. As a phylogenetic relict, it is the only known surviving member of its order.

Behavior section[edit]

... In a threat response called the "pumpkin" or "pineapple" posture, the vampire squid inverts its caped arms back over the body, presenting an ostensibly larger form covered in fearsome-looking though harmless spines (called cirri). The underside of the cape is heavily pigmented, masking most of the body's photophores. The glowing arm tips are clustered together far above the animal's head, diverting attack away from critical areas. If a predator were to bite off an arm tip, the vampire squid can regenerate it. The vampire squid's retractile filaments have been suggested to play a larger role in predator avoidance via both detection and escape mechanisms.

Discovery section[edit]

The vampire squid was discovered during the Valdivia Expedition (1898–1899), led by Carl Chun.

Chun later classified the Vampire squid into its family Vampyroteuthidae.

Chun was a zoologist who was inspired by the Challenger Expedition, and wanted to verify that life does indeed exist below 300 fathoms (550 meters). This expedition was funded by the German society Gesellschaft Deutscher Naturforscher und Ärzte, a group of German scientists that believed there was life at depths greater than 550 meters, contrary to the Abyssus theory. The S.S. Valdivia was fitted with equipment for the collection of deep sea organisms, as well as laboratories and specimen jars, in order to analyze and preserve what was caught. The voyage began in Hamburg, Germany, followed by Edinburgh, and then traced around the west coast of Africa. After navigating around the southern point of Africa, the expedition studied deep areas of the Indian and Antarctic Ocean.

Conservation status[edit]

The vampire squid is currently not on any endangered or threatened species list and they have no known impact on humans. Microplastic contamination in the ocean is suggested to impact the health of the Vampire squid. The vampire squid can consume micro-plastics via both prior contaminated prey/food as well as microplastics in the water column.

Bibliography

• Article 1: Ferreira, G. V., et al. (2022). Plastic in the inferno: Microplastic contamination in deep-sea cephalopods (Vampyroteuthis infernalis and Abralia veranyi) from the southwestern Atlantic. Marine pollution bulletin, 174, 113309. doi.org/10.1016/j.marpolbul.2021.113309.
  • Pollution impact on vampire squids and conservation status.
  • Microplastic contamination within the ocean is an important environmental concern. This article evaluates microplastic contamination in the deep sea species Vampyroteuthis infernalis (Vampire squid).