Octopus tetricus

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Octopus tetricus
Octopus tetricus 118664956.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Order: Octopoda
Family: Octopodidae
Genus: Octopus
Species:
O. tetricus
Binomial name
Octopus tetricus
Gould, 1852 [1]
Synonyms [2]

Octopus gibbsiO'Shea, 1999

Octopus tetricus, the gloomy octopus, the common Sydney octopus, [3] or the peachy octopus, [4] is a species of octopus from the subtropical waters of eastern Australia and northern New Zealand. [2] O.tetricus belongs to the Octopus vulgaris species group. All species within the O. vulgaris group are similar in morphology, [5] behaviour, and physiology. [6] The English translation of O. tetricus (Latin) is 'the gloomy octopus'. [7] It is a significant species in the fishing industry in Australia. They play an important role in energy flux between trophic levels in the marine environment. [8]

Contents

Distribution

O. tetricus was originally discovered in New South Wales and was also found along the eastern Australian coastline. It occurs from Lakes Entrance in Victoria [7] to Moreton Bay in southern Queensland. [6] O. tetricus is distributed in the subtropical seas of eastern Australia and northern New Zealand, including Lord Howe Island. A close relative, Octopus djinda , occurs at similar latitudes in Western Australia, from Shark Bay to Cape Le Grand, [7] and was considered to be conspecific with O. tetricus until 2021.The first sighting of O. tetricus in New Zealand wasn't until 1997, [4] and has since become one of the most common species of octopus found in New Zealand, alongside Pinnoctopus cordiformis and Macroctopus maorum . [9] O. tetricus populations in New Zealand are found along the North-East coast of the North Island, between the Bay of Plenty and Northland. [10]

Gene squencing confirms that O. tetricus from Australia and New Zealand come from the same original population. It is proposed that the mechanism for gene flow across the Tasman Sea is through planktonic larve and/or adults using floating wood or algae as transport. [11] It is hypothesised that warmer waters spreading south of Australia are influencing populations to O. tetricus to disperse further south in response to climate change.

Anatomy and morphology

A gloomy octopus under a rock in Clovelly Pool, Sydney Gloomy Octopus-Octopus tetricus.JPG
A gloomy octopus under a rock in Clovelly Pool, Sydney
Octopus tetricus observed north of Auckland, New Zealand. Octopus tetricus New Zealand 181759846.jpg
Octopus tetricus observed north of Auckland, New Zealand.

Octopus tetricus is normally coloured grey to mottled brown with rufous arm faces that taper towards the tip. They have orange colouration of arms, funnel, and mantle opening. [10] Their eyes are typically white in colour. The skin is granular, and has many small irregularly shaped patches and large warty structures used to make it appear spiky when the octopus camouflages itself as seaweed. [3] The adults typically have a tentacle span of 2 metres (6.6 ft) [12] and a mantle length of up to 20 cm. [13] The maximum weight recorded for O. tetricus is 2.6kg. [11]

The second and third arms of O. tetricus are longer than the first and fourth arms, typical of all species in the Octopoda order. [14] The brain, optic lobes, and the highly developed arm nervous system are the three main components of the octopus nervous system. [15] Each arm of the octopus has been described as having its own brain, where individual processing, motor systems, and sensory exploration can occur. This is where the concept that octopus have many brains comes from. [15] The arm nervous system of the octopus contains three-fifths of the octopus's total number of neurons - 350 million neurons distributed equally throughout each of its eight arms.

Taxonomy and etymology

Octopus tetricus Gould, 1852 was described by American conchologist Augustus Addison Gould in the 1852 publication, Mollusca of the United States Exploring Expedition under Captain Charles Wilkes. [16] An illustration of O. tetricus was also published a few years later (plate 47). [17]

The type specimen is listed as being from Sydney, New South Wales, Australia. [16] The type was one of many thousands of specimens collected by the Wilkes Expedition, however this particular specimen of O. tetricus is thought to be lost. [18] [19]

The New Zealand species O. gibbsii is considered to be a synonym of O. tetricus. [20]

Gloomy octopus in a rock pool north of Auckland, New Zealand. Octopus tetricus New Zealand 249300376.jpg
Gloomy octopus in a rock pool north of Auckland, New Zealand.
Octopus tetricus in a rock pool in Northland, New Zealand. Octopus tetricus New Zealand 346252155.jpg
Octopus tetricus in a rock pool in Northland, New Zealand.

The species epiethet tetricus means 'forbidding' or 'gloomy'. [7]

Life cycle

Reproduction and growth

The reproductive cycle of females is tied to seasonal changes, similar to many other species. Females reach maturity around Australia's spring and summer seasons in order to mate and lay eggs. [21] During the mating process the male O. tetricus passes spermatophores to the female in two different ways. The male either wraps his arms and web around the female's mantle or reaches his mating arm from a distance and inserts it into the female's mantle. The males third right arm is the specialised mating arm, and the sperm is moved down a groove on this arm which has a sucker-less tip. [13] [14] Spermatophores are released from the male's "terminal organ", moved by the male's oral suckers, and then the spermatophores are inserted into the female's oviduct. [22]

O. tetricus start out as eggs that are laid in large numbers in the octopus's nest, approximately 270,000 eggs per female. [11] The eggs are normally glued to the rock or substrate at the top of the den created by the female octopus. The female usually lays her eggs over several nights in a string formation. The size and number of strings of eggs usually depends on how large the female is and can have between 60 and 200 egg strings. The female then guards the eggs until they hatch. [23] Female O. tetricus have also been known to store viable spermatozoa for up to 114 days. The amount of time embryonic development takes varies with water temperature, and newly hatched O. tetricus larvae are about 2.5 mm long and 1.1mm wide, [24] approximately the size of a grain of rice. These larvae go through a stage called the paralarval stage where they are considered planktonic, or free floating, organisms before they settle to the bottom and grow large enough to hunt for their food. This stage may last around 35–60 days. [8] The females of O. tetricus have been known to cannibalise the males following mating. [3]

Temperature plays a key role in growth of this octopus species. With a good food supply, octopuses that reside in areas with a cooler water temperature tend to grow slower during the key growth phase and when they reach maturity they are generally larger than octopuses that are found in warmer water temperatures. [8]

Lifespan

Adult O. tetricus is observed to have a relatively small body size and a lifespan of approximately 11 months, [21] although there is evidence that they can live up to 2 years. [10] They have a very fast growth rate, reaching adult size after approximately 100 days. [8] Female O. tetricus rarely eat or sleep during the protection of the nest, devoting all resources to nourishing its offspring, and die shortly after the eggs hatch. [23] Females are found to mature at a slower rate and become larger than male O. tetricus. [21] This is a semelparous species, meaning each female reproduces once in her lifetime. [11]

Habitat and behavioural ecology

Habitat

Octopus tetricus occurs in the intertidal zone along rocky shores and seagrass beds, and in the ocean, out up to 70m, [11] and it has been suggested that this species is associated more commonly with rocky reefs during the breeding season, although they frequent areas of the sea bed with soft-sediments for much of their life. [3] O. tetricus alter their habitats by digging out dens and using remains from prey, including but not limited to shells. It is very common for scallop beds to be found in close proximity to the excavated dens. The scallops serve as a food source and their shells are part of the shell beds built. One O. tetricus den in Sydney has been observed being continuously used by different individuals since at least 2009. [25] O. tetricus has been observed shifting and transporting sediment and shells to maintain their dens. They tend to have a preference for materials that are free from barnacles and encrustations, although the scale on which this is the case is dependent on foraging success. [13]

This species can be found across a variety of coastal environments all year round, but there are some observations of adults aggregating inshore for breeding purposes during spring and summer. Most individuals have high site fedility, staying in the same location for an average of 3 months. These movements in and out of coastal areas and deeper ocean depths could potentially correlate with the stages of lifecycle they are currenty in. [11] Life cycle stage also influences the position which they sit inside their dens, where brooding females will sit close to the entrance as a means of protecting the eggs compared to non-brooding females that reside near the back of the den. [10] Females must defend their eggs from other males of the same species, but also other marine dwelling organisms, such as eels. [10]

This species of octopus is considered to be an ecosystem engineer. This means that the way they create their habitats influences and builds an ecosystem around their dwellings. They carry their prey, often shellfish, on their back and discard the empty shells at their dens when they have finished eating. [25] The shell beds that are created around the excavated dens attract hermit crabs and fish due to the various hiding places created. Small fish and other small prey species attract larger species and the cycle builds, creating an ecosystem. [26] A solid object can serve as a good den that can also be the start of a new settlement for O. tetricus. [13] Studies show that O. tetricus has higher populations in patch reef habitats than broken reef habitats, and were scarcely found on flat reefs. Adult O. tetricus were also found to occupy coastal reefs in the summer and then disappear around the second week of April, which is the second week of autumn in Australia. [10] Shelters serve a vital role in octopus ecology. When resources are scarce, such as food and dens, they will often attempt to exclude and displace other individuals. [26]

Social behaviour and mating

Scientists have observed many different behaviours exhibited by O. tetricus including, signalling, mating, mate defence, and aggression. Some have even observed an octopus evicting another from its den. Occasionally this aggressive behaviour led to physical altercations between octopuses. [25] The likelihood of an aggressive encounter leading to a physical altercation is increased when there is a significance difference in the relative darkness of body patterning between the two individuals. The octopus which is paler in colouration is much more likely to retreat and back down, avoiding a fight. Grappling and physical contact between octopus is much more common when the relative difference in darkness is much smaller. [11] Although uncommon, there is some evidence that occasional male-female aggression occurs during mating attempts. [13] This darkening of skin colour when aggressive has been explained by chromatophore muscle tension. Physical displays of aggression also include seeking higher ground, elevated posture by standing up on extended arms, and spreading webbing and raising arms. [11] In general, the species will avoid aggressive encounters, as they have a high cost to reward ratio and can also result in physical damage to their body. [27]

It is a territorial species which sits out the day in a lair among rocks and rubble, the rubble being collected to create a defensible lair. The lairs of this species can be identified by the shells of the octopus's prey which it scatters around its home. They move about the rocks by crawling using their arms but they can use their siphon to propel themselves through the water by generating a jet of water or to move (throw) shells, silt, and algae, sometimes targeting other individual octopus. [3] [28] Throwing is a very rare and uncommon behaviour exhibited in non-humans, only seen in a few other species such as non-human primates and dolphins. [28] Shells are the most common object thrown, and most of throws are done in some social context, rather than a solitary individual. Some throws, however, are in the context of den cleaning by the individual. They can display high-vigor or low-vigor throws, depending on the context (e.g., den cleaning or aiming towards another individual). They can also display warning throws, where they lift their throwing arm just before actually hurling an object. Individuals that are hit or have the potential to be hit respond in various ways, such as moving, ducking, raising arms, or changing their movements. [28] There have been several observations of O. tetricus evicting each other from their dens and claiming it for themselves, forcing the evicted individual into finding a new den elsewhere. Commonly, those individuals in neighbourning dens tend to mate more than individuals in dens further apart. [25]

Observation of mating behaviours has revealed that O. tetricus females have a stronger precopulatory preference for males that have longer mating appendages, or ligulae. It is a polygynandrous species - both female and male octopuses mate multiple times with different partners throughout a mating season. Female octopuses are able to accept multiple spermatophores from males but they only produce one brood of eggs at the end of a mating season. [29] Females have also been observed storing sperm for up to 3 months after mating, before laying any eggs. [11] Once the males have deposited the sperm in the female, the females receive no parental care help from the male – she is solely responsible for the eggs. [30]

The species is generally known to be solitary, but complex social behaviours have been observed by scientists. [25]

Feeding and hunting

Octopus tetricus is primarily a nocturnal feeder which uses its sharp beak to feed on crustaceans and molluscs, for example sea snails and bivalves. It has also been recorded as being cannibalistic, [3] sometimes preying on smaller individuals and consuming their limbs. [10] It's primary prey is shellfish, such as scallops, and crustaceans, such as lobster, however it's diet is heavily influenced by prey availability. They have also been observed eating sea horses on multiple occasions in New South Wales. [11] The metabolism of an octopus is driven by protein, and it is considered a carnivorous species. O. tetricus predation influences hermit and lobster densities and habitat choice, modifying ecosystem dyanmics and trophic interactions of various species. [26] O. tetricus return to their den after hunting to consume their prey in safety.

Two areas in Jervis Bay where they congregate have been dubbed Octopolis and Octlantis, [13] [25] containing a large area of discarded shells where ten or more octopuses den and mate. [31] [32]

Animals that predate on O. tetricus include some species of dolphin, the short-tail stingray (Dasyatis brevicaudata), southern eagle rays (Myliobatis goodei), wobbegong sharks, and some fish. Fish, however, usually attack when in schools, such as Chinaman leather-jackets. [33] There is no evidence to suggest that any one species soley relies on O. tetricus as a food source.

Generally, O. tetricus are considered a solitary, crespular species, meaning they emerge from their dens to hunt and feed alone at dusk and dawn before returning to the safety of their enclosures to consume prey and to spend their daytime. Contrary to this, it is believed that the solitary, nocturnal behaviour is context-dependent. In high densities of the species, individuals become much more social and active during the day. This could be due to a greater sense of safety and protection when in larger groups. [11] [26] High density aggregations of the species is most common when there is limited den opportunities and plentiful food abundance.

O. tetricus regulate energy flux between trophic levels within the marine ecosystem by mediating the amount of prey that can be consumed by other octopus species. This is done by competing with other species for the prey, such as scallops and crabs. [25]

Personality and intelligence

Octopus tetricus, like all octopus, show remarkable intelligence and cognitive abilities. Although they are solitary, they have very complex social interactions and dynamics. Octopus rely majorly on visual cues when detecting predators and prey, using polarised light. [27] O. tetricus display episodic personality, meaning that they alter and change their behaviour based on the environment and circumstances of the octopus at the time. It was inconclusive whether they have individual personalities, and more research is needed in this field. [27] There have been observations of O. tetricus luring prey by moving and wiggling its arms, although it is not definitive that they were genuinely trying to lure in prey. This may have been unintentional. [34] Differences in behaviour between sexes of the species are apparent, such as males being less likely to modify dens and shelters compared to females. [10]

The ability of O. tetricus to quickly modify the pattern, colour, and texture of their skin is a tool for signalling to other octopus, as well as crypsis which is used for both anti-predator and predation strategies. [35] Using properties of skin is a significant element to both combative and courtship types of behaviour. They are also able to communicate with other octopus without disrupting their crypsis, meaning they do not have to be vulnerable in order to communicate with each other. [36] Changes in skin properties can be used to signal that they feel threatened, for example when faced with a predator, or when a female rejects a males advances for mating. However, it does not play a role in females selecting male mating partners.

Fisheries

Octopus tetricus may be caught as bycatch in trawl and lobster-pot fisheries and is then sold for both human consumption and for use as bait. [3] The species made up to 43% of total cephalopod fishing catches in 2007, however, it is possible that O. tetricus was sometimes misidentified as Octopus australis . [11] Since 2016, annual catches of the species has increased over 50% to 12.6 tonnes. [11] In 2017, it was said that O. tetricus made up 14% of the total octopus catch. [8] Their catch rates are highest during spring and summer, by which they then drop significantly just as autumn arrives. [10] Historically and through to the present day, the species is a significantly important species in the fishing industry across Australia.

Conservation status

Octopus tetricus is listed as 'Least Concern' on The IUCN Red List of Threatened Species. [37]

Related Research Articles

<span class="mw-page-title-main">Octopus</span> Soft-bodied eight-limbed order of molluscs

An octopus is a soft-bodied, eight-limbed mollusc of the order Octopoda. The order consists of some 300 species and is grouped within the class Cephalopoda with squids, cuttlefish, and nautiloids. Like other cephalopods, an octopus is bilaterally symmetric with two eyes and a beaked mouth at the centre point of the eight limbs. The soft body can radically alter its shape, enabling octopuses to squeeze through small gaps. They trail their eight appendages behind them as they swim. The siphon is used both for respiration and for locomotion, by expelling a jet of water. Octopuses have a complex nervous system and excellent sight, and are among the most intelligent and behaviourally diverse of all invertebrates.

<span class="mw-page-title-main">Cephalopod</span> Class of mollusks

A cephalopod is any member of the molluscan class Cephalopoda such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral body symmetry, a prominent head, and a set of arms or tentacles modified from the primitive molluscan foot. Fishers sometimes call cephalopods "inkfish", referring to their common ability to squirt ink. The study of cephalopods is a branch of malacology known as teuthology.

<i>Grimpoteuthis</i> Genus of cephalopods known as the dumbo octopuses

Grimpoteuthis is a genus of pelagic cirrate (finned) octopods known as the dumbo octopuses. The name "dumbo" originates from their resemblance to the title character of Disney's 1941 film Dumbo, having two prominent ear-like fins which extend from the mantle above each eye. There are 17 species recognized in the genus.

<span class="mw-page-title-main">Southern blue-ringed octopus</span> Species of mollusc

The southern blue-ringed octopus is one of three highly venomous species of blue-ringed octopuses. It is most commonly found in tidal rock pools along the south coast of Australia. As an adult, it can grow up to 20 centimetres (8 in) long and on average weighs 26 grams (0.9 oz). They are normally a docile species, but they are highly venomous, possessing venom capable of killing humans. Their blue rings appear with greater intensity when they become aggravated or threatened.

<span class="mw-page-title-main">Giant Pacific octopus</span> Species of cephalopod

The giant Pacific octopus, also known as the North Pacific giant octopus, is a large marine cephalopod belonging to the genus Enteroctopus and Enteroctopodidae family. Its spatial distribution encompasses much of the coastal North Pacific, from the Mexican state of Baja California, north along the United States' West Coast, and British Columbia, Canada; across the northern Pacific to the Russian Far East, south to the East China Sea, the Yellow Sea, the Sea of Japan, Japan's Pacific east coast, and around the Korean Peninsula. It can be found from the intertidal zone down to 2,000 m (6,600 ft), and is best-adapted to colder, oxygen- and nutrient-rich waters. It is the largest octopus species on earth and can often be found in aquariums and research facilities in addition to the ocean. E. dofleini play an important role in maintaining the health and biodiversity of deep sea ecosystems, cognitive research, and the fishing industry.

<i>Octopus cyanea</i> Species of cephalopod known as the big blue octopus

Octopus cyanea, also known as the big blue octopus or day octopus, is an octopus in the family Octopodidae. It occurs in both the Pacific and Indian Oceans, from Hawaii to the eastern coast of Africa. O. cyanea grows to 16 cm in mantle length with arms to at least 80 cm. This octopus was described initially by the British zoologist John Edward Gray in 1849; the type specimen was collected off Australia and is at the Natural History Museum in London.

<span class="mw-page-title-main">Common blanket octopus</span> Species of cephalopod

The common blanket octopus or violet blanket octopus is a large octopus of the family Tremoctopodidae found worldwide in the epipelagic zone of warm seas. The degree of sexual dimorphism in this species is very high, with females growing up to two meters in length, whereas males grow to about 2.4 cm. The first live specimen of a male was not seen until 2002 off the Great Barrier Reef. Individual weights of males and females differ by a factor of about 10,000 and potentially more.

<i>Macroctopus</i> Species of mollusc

Macroctopus maorum is known more commonly as the Maori octopus or the New Zealand octopus. It is found in the waters around New Zealand and southern Australia. M. maorum is one of the largest and most aggressive octopus species living in the New Zealand and Australian waters. They feed mainly on crustaceans and fish. Although they have a short life span, the females lay thousands of eggs and are very protective of them.

<i>Callistoctopus ornatus</i> Species of mollusc

Callistoctopus ornatus is a tropical species of octopus native to the Indo-Pacific region. Other common names include white-striped octopus and night octopus, in reference to its nocturnal habits. It was previously known as Polypus ornatus. C. ornatus is edible and was recorded in a Hawaiian market in 1914 by S. S. Berry.

<i>Vulcanoctopus</i> Species of benthic octopus

Vulcanoctopus hydrothermalis, also known as the vent octopus, is a small benthic octopus endemic to hydrothermal vents. It is the only known species of the genus Vulcanoctopus. This vent octopus is endemic to the hydrothermal vent habitat that is located in the East Pacific Rise.

<i>Abdopus aculeatus</i> Species of cephalopod

Abdopus aculeatus is a small species of octopus in the order Octopoda. It has the common name algae octopus due to its typical resting camouflage, which resembles a gastropod shell overgrown with algae. It is small in size with a mantle around the size of a small orange and arms 25 cm in length, and is adept at mimicking its surroundings.

<span class="mw-page-title-main">Octopus minor</span> Species of cephalopod

Octopus minor, also known as the long arm octopus or the Korean common octopus, is a small-bodied octopus species distributed along the benthic coastal waters bordering China, Japan, and the Korean Peninsula. It lives at depths ranging from 0 to 200 metres. O. minor is commonly found in the mudflats of sub-tidal zones where it is exposed to significant environmental variation. It is grouped within the class Cephalopoda along with squids and cuttlefish.

<span class="mw-page-title-main">Larger Pacific striped octopus</span> Species of octopus

The larger Pacific striped octopus (LPSO), or Harlequin octopus, is a species of octopus known for its intelligence and gregarious nature. The species was first documented in the 1970s and, being fairly new to scientific observation, has yet to be scientifically described. Because of this, LPSO has no official scientific name. Unlike other octopus species which are normally solitary, the LPSO has been reported as forming groups of up to 40 individuals. While most octopuses are cannibalistic and have to exercise extreme caution while mating, these octopuses mate with their ventral sides touching, pressing their beaks and suckers together in an intimate embrace. The LPSO has presented many behaviors that differ from most species of octopus, including intimate mating behaviors, formation of social communities, unusual hunting behavior, and the ability to reproduce multiple times throughout their life. The LPSO has been found to favor the tropical waters of the Eastern Pacific.

<i>Wunderpus photogenicus</i> Species of cephalopod

Wunderpus photogenicus, the wunderpus octopus, is a small-bodied species of octopus with distinct white and rusty brown coloration. 'Wunderpus' from German "wunder" meaning 'marvel or wonder'.

<i>Octopus bimaculatus</i> Species of octopus

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<i>Opisthoteuthis agassizii</i> Species of octopus

Opisthoteuthis agassizii is a lesser-known, deep-sea octopus first described in 1883 by Addison E. Verrill.

<i>Bathypolypus sponsalis</i> Species of mollusc

Bathypolypus sponsalis, commonly called the globose octopus, is a deep sea cephalopod that can be found in both the eastern Atlantic Ocean and the Mediterranean Sea. It possesses many morphological traits adapted to a deep sea environment, including large eggs, reduced gills, no ink sac, and subgelatinous tissues. A distinguishing factor are the relatively large reproductive organs. Their diet consists of predominantly crustaceans and molluscs, but they sometimes consume fish as well. Bathypolypus sponsalis usually dies quickly after reproduction and only spawns once in their lifetime. Sexually mature females have a mantle length of at least 34 mm and sexually mature males have a mantle length of about 24 mm. Juveniles are white and transition to dark brown then to dark purple once maturity is reached.

Opisthoteuthis massyae is an octopus living in the eastern Atlantic Ocean.

Abdopus capricornicus is a species of octopus in the family Octopodidae, and is often also referred to as Octopus capricornicus. This octopus is native to the Great Barrier Reef and is often found throughout the Indo-West Pacific Ocean. There are six other species of octopuses within the subgenus Abdopus with a large number of organisms not yet described. This octopus is notable for its unique body patterning through which it can change. The likely uses for this characteristic are camouflage or intraspecific communication. Other organisms in the Abdopus genus include A. horridus, A. abaculus, A. aculeatus, and A. tonganus. Individuals are capable of autotomy, sacrificing a writhing arm to a predator to distract it while making an escape.

<i>Octopus hubbsorum</i> Species of Octopus

Octopus hubbsorum, is an octopus in the family Octopodidae. It is commonly found along tropical waters along the central Pacific Coast of Mexico. Here, they are one of the most commonly caught cephalopods and are commercially extremely important for the economy.

References

  1. ↑ "ITIS standard report - Octopus tetricus (Gould, 1852)". Integrated Taxonomic Information System . Retrieved 12 October 2014.
  2. 1 2 "Octopus tetricus Gould, 1852". World Register of Marine Species. Vlaams Instituut voor de Zee. Retrieved 29 January 2017.
  3. 1 2 3 4 5 6 7 "Common Sydney Octopus – Octopus tetricus". Australian Museum. 2012. Retrieved 29 January 2018.
  4. 1 2 Patterson, S M (2022). "Novel Drone Technology Improves Habitat Mapping for a Coastal Octopus Species". Auckland University of Technology.
  5. ↑ Amor, Michael D.; Norman, Mark D.; Roura, Alvaro; Leite, Tatiana S.; Gleadall, Ian G.; Reid, Amanda; Perales-Raya, Catalina; Lu, Chung-Cheng; Silvey, Colin J.; Vidal, Erica A. G.; Hochberg, Frederick G. (2017). "Morphological assessment of the Octopus vulgaris species complex evaluated in light of molecular-based phylogenetic inferences". Zoologica Scripta. 46 (3): 275–288. doi:10.1111/zsc.12207. hdl: 11343/291747 . ISSN   1463-6409. S2CID   88706796.
  6. 1 2 Amor MD; Norman MD; Cameron HE; Strugnell JM (2014-06-25). "Allopatric speciation within a cryptic species complex of Australasian octopuses". PLOS ONE. 9 (6): e98982. Bibcode:2014PLoSO...998982A. doi: 10.1371/journal.pone.0098982 . PMC   4070898 . PMID   24964133.
  7. 1 2 3 4 Amor, Michael D.; Hart, Anthony M. (2021-11-03). "Octopus djinda (Cephalopoda: Octopodidae): a new member of the Octopus vulgaris group from southwest Australia". Zootaxa. 5061 (1): 145–156. doi:10.11646/zootaxa.5061.1.7. ISSN   1175-5334. PMID   34810636. S2CID   243468570.
  8. 1 2 3 4 5 Ramos JE; Pecl GT; Moltschaniwskyj NA; et al. (2014). "Body size, growth and life span: implications for the polewards range shift of Octopus tetricus in south-eastern Australia". PLOS ONE. 9 (8): e103480. Bibcode:2014PLoSO...9j3480R. doi: 10.1371/journal.pone.0103480 . PMC   4121162 . PMID   25090250.
  9. ↑ Vennell, Robert (5 October 2022). Secrets of the Sea: The Story of New Zealand's Native Sea Creatures. HarperCollins Publishers Ltd. pp. 118–125. ISBN   978-1-77554-179-0. LCCN   2021388548. Wikidata   Q114871191.
  10. 1 2 3 4 5 6 7 8 9 Anderson TJ (April 30, 1997). "Habitat selection and shelter use by Octopus tetricus". Marine Ecology Progress Series. 150: 137–48. Bibcode:1997MEPS..150..137A. doi: 10.3354/meps150137 .
  11. 1 2 3 4 5 6 7 8 9 10 11 12 13 Hall, K C; Moltschaniwskyj, N A (September 27, 2024). Octopus Biology and Ecology. Elsevier. pp. 167–176. ISBN   9780128208946.{{cite book}}: CS1 maint: date and year (link)
  12. ↑ "Atlas of Living Australia - Octopus tetricus (Gould, 1852)". Atlas of Living Australia . Retrieved 26 October 2014.
  13. 1 2 3 4 5 6 Godfrey-Smith P; Lawrence M (2012-07-01). "Long-term high-density occupation of a site by Octopus tetricus and possible site modification due to foraging behavior". Marine and Freshwater Behaviour and Physiology. 45 (4): 1–8. Bibcode:2012MFBP...45....1G. doi:10.1080/10236244.2012.727617. ISSN   1023-6244. S2CID   83893501.
  14. 1 2 Budelmann, Bernd-Ulrich (1978-12-01). "Octopus. physiology and behaviour of an advanced invertebrate: M.J. Wells. Chapman and Hall, London. (Distributed in the U.S.A. by Halsted Press, John Wiley and Sons, New York, N.Y.). 1978, 431 pp., 42 tables, 164 figures, 6 plates (2 coloured, 4 black and white), £17.00, SBN 412-13260-5-111". Behavioural Processes. 3 (4): 356–357. doi:10.1016/0376-6357(78)90009-8. ISSN   0376-6357.
  15. 1 2 Carls-Diamante, Sidney (2022-03-14). "Where Is It Like to Be an Octopus?". Frontiers in Systems Neuroscience. 16. doi: 10.3389/fnsys.2022.840022 . ISSN   1662-5137. PMC   8988249 . PMID   35401127.
  16. 1 2 Gould, A.A. (1852). Mollusca of the United States Exploring Expedition under Captain Charles Wilkes. Mollusca of the Wilkes Expedition. Vol. 12. Philadelphia: Printed by C. Sherman. p. 474.
  17. ↑ Gould, A.A. (1856). United States exploring edition. Mollusca and Shells Atlas. Vol. 12. Philadelphia: Printed by C. Sherman. pp. plate 47.
  18. ↑ Johnson, Richard I. (1964-01-01). "The Recent Mollusca of Augustus Addison Gould". Bulletin of the United States National Museum (239): 1–182. doi:10.5479/SI.03629236.239.
  19. ↑ Voss, Nancy A.; Sweeney, M. J. (1998-01-01). "Systematics and Biogeography of cephalopods. Volume II". Smithsonian Contributions to Zoology (586): 277–599. doi:10.5479/SI.00810282.586.277.
  20. ↑ Amor, Michael D.; Norman, Mark D.; Cameron, Hayley E.; Strugnell, Jan (2014-06-25). "Allopatric speciation within a cryptic species complex of Australasian octopuses". PLOS ONE. 9 (6): e98982. Bibcode:2014PLoSO...998982A. doi: 10.1371/JOURNAL.PONE.0098982 . PMC   4070898 . PMID   24964133.
  21. 1 2 3 Ramos Castillejos JE (2015). Life-history and population dynamics of the range extending Octopus tetricus (Gould, 1852) in south-eastern Australia (Ph.D. thesis). University of Tasmania.
  22. ↑ Huffard CL; Godfrey-Smith P (2010). "Field observations of mating in Octopus tetricus Gould, 1852 and Amphioctopus marginatus (Taki, 1964) (Cephalopoda: Octopodidae)". Molluscan Research. 30 (2): 81–86. doi:10.11646/mr.30.2.3. S2CID   266214974 – via ResearchGate.
  23. 1 2 Spreitzenbarth, Stefan; Jeffs, Andrew (2020-09-15). "Egg survival and morphometric development of a merobenthic octopus, Octopus tetricus, embryos in an artificial octopus egg rearing system". Aquaculture. 526: 735389. Bibcode:2020Aquac.52635389S. doi:10.1016/j.aquaculture.2020.735389. ISSN   0044-8486. S2CID   219088008.
  24. ↑ Joll LM (1976). "Mating, egg-laying and hatching of Octopus tetricus (Mollusca: Cephalopoda) in the laboratory". Marine Biology. 36 (4): 327–333. Bibcode:1976MarBi..36..327J. doi:10.1007/bf00389194. ISSN   0025-3162. S2CID   83838409.
  25. 1 2 3 4 5 6 7 Scheel D; Chancellor S; Hing M; et al. (2017-07-04). "A second site occupied by Octopus tetricus at high densities, with notes on their ecology and behavior". Marine and Freshwater Behaviour and Physiology. 50 (4): 285–291. Bibcode:2017MFBP...50..285S. doi:10.1080/10236244.2017.1369851. ISSN   1023-6244. S2CID   89738642.
  26. 1 2 3 4 Scheel D; Godfrey-Smith P; Lawrence M (2014-12-30). "Octopus tetricus (Mollusca: Cephalopoda) as an ecosystem engineer". Scientia Marina. 78 (4): 521–528. doi: 10.3989/scimar.04073.15A . ISSN   1886-8134.
  27. 1 2 3 Pronk, R.; Wilson, D. R.; Harcourt, R. (2010-04-01). "Video playback demonstrates episodic personality in the gloomy octopus". Journal of Experimental Biology. 213 (7): 1035–1041. doi:10.1242/jeb.040675. ISSN   1477-9145. PMID   20228339.
  28. 1 2 3 Godfrey-Smith, Peter; Scheel, David; Chancellor, Stephanie; Linquist, Stefan; Lawrence, Matthew (2022). "In the line of fire: Debris throwing by wild octopuses". PLOS ONE. 17 (11): e0276482. Bibcode:2022PLoSO..1776482G. bioRxiv   10.1101/2021.08.18.456805 . doi: 10.1371/journal.pone.0276482 . PMC   9645608 . PMID   36350820.
  29. ↑ Morse P (2008). Female Mating Preference, Polyandry, and Paternity Bias in Octopus tetricus (Honors Thesis). University of Western Australia, Perth. pp. 1–97.
  30. ↑ Boyle, P. R., ed. (1983). Cephalopod life cycles. London ; New York: Academic Press. ISBN   978-0-12-123001-2.
  31. ↑ Main D (28 January 2016). "Octopuses More Social Than Thought, Denizens of 'Octopolis' Prove". Newsweek. Retrieved 14 September 2017.
  32. ↑ Stokstad E (13 September 2017). "Scientists discover an underwater city full of gloomy octopuses". Sciencemag. Retrieved 14 September 2017.
  33. ↑ Scheel, David; Godfrey-Smith, Peter; Lawrence, Matthew (2014-12-30). "Octopus tetricus (Mollusca: Cephalopoda) as an ecosystem engineer". Scientia Marina. 78 (4): 521–528. doi: 10.3989/scimar.04073.15A . ISSN   1886-8134.
  34. ↑ Godfrey-Smith, Peter (2019-01-01). "Octopus experience". Animal Sentience. 4 (26). doi: 10.51291/2377-7478.1503 . ISSN   2377-7478.
  35. ↑ Mäthger, Lydia M.; Hanlon, Roger T. (2007-07-01). "Malleable skin coloration in cephalopods: selective reflectance, transmission and absorbance of light by chromatophores and iridophores". Cell and Tissue Research. 329 (1): 179–186. doi:10.1007/s00441-007-0384-8. ISSN   1432-0878. PMID   17410381.
  36. ↑ Mäthger, Lydia M; Hanlon, Roger T (2006-12-22). "Anatomical basis for camouflaged polarized light communication in squid". Biology Letters. 2 (4): 494–496. doi:10.1098/rsbl.2006.0542. ISSN   1744-9561. PMC   1834008 . PMID   17148271.
  37. ↑ The IUCN Red List of Threatened Species 2018.1. 2018-07-05.
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