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. 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. Once she does, she may need to brood over them for up to days before they hatch. Their reproductive strategy appears to be of the iteroparous type, which is an exception amongst the otherwise semelparous Coleoidea.
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.
Hatchlings are about 8 mm in length and are well-developed miniatures of the adults, with some differences. Their arms lack webbing, their eyes are smaller, and their velar filaments are not fully formed. The hatchlings are transparent and survive on a generous internal yolk for an unknown period before they begin to actively feed.
The smaller animals frequent much deeper waters, perhaps feeding on marine snow falling organic detritus. The mature vampire squid is also thought to be an opportunistic hunter of larger prey as fish bones, other squid flesh, and gelatinous matter has been recorded in mature vampire squid stomachs.
Reproduction of the vampire squid is unlike any other coleoid cephalopod. When the female is ready, she will use the packet to reproduce. These spawning events happen quite far apart due to the vampire squid's low metabolic rate, meaning they take a long time to accumulate the necessary resources to spawn. This is very rare and needs further research done on it.
The vampire squid was discovered during the Valdivia Expedition — , led by Carl Chun. Chun was a zoologist who was inspired by the Challenger Expedition, and wanted to verify that life does indeed exist below fathoms meters.
The 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.
They have eight arms but lack feeding tentacles, and instead use two retractile filaments in order to capture food. This deep-water lifestyle might explain why the squid survived the crisis that killed the nonavian dinosaurs at the end of the Cretaceous period , he added. He and his colleagues are now attempting to make similar connections for cuttlefish, a group of cute, color-changing cephalopods whose origins are similarly murky.
Stephanie Pappas is a contributing writer for Live Science covering topics from geoscience to archaeology to the human brain and behavior. A freelancer based in Denver, Colorado, she also regularly contributes to Scientific American and The Monitor, the monthly magazine of the American Psychological Association.
Stephanie received a bachelor's degree in psychology from the University of South Carolina and a graduate certificate in science communication from the University of California, Santa Cruz. Live Science. Nor can it change color to confuse intruders the way its shallow-water cousins can; living as it does in the deep ocean, where little light penetrates , color-changing is a pointless strategy. Instead, the vampire squid squirts a copious cloud of sticky, bioluminescent mucus toward would-be predators and the occasional research ROV.
On the freshwater side, the vampire fish is a nickname for the payara, an abundant gamefish found in the Amazon Basin.
When exhibiting this posture, this species looks rather intimidating, but it is actually quite harmless. It is not predatory. Instead, it depends on food particles that it captures using sticky cells on its long, filamentous tentacles.
In this way, it opportunistically feeds on plant and animal matter that sinks from the surface ocean. Some large fishes and diving predators are known to eat vampire squids. Unlike shallow-water squids and octopuses, vampire squids do not expel black ink to escape predation.
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