Octopus Vulgaris (Common Octopus) Cuvier, 1797

DWhatley

Kraken
Staff member
Moderator
Joined
Sep 4, 2006
Messages
20,698
Reaction score
1,833
Location
Gainesville, GA
Classic Camouflage Video by Roger Hanlon

Interview with Dr Hanlon that includes a brief discussion on capturing his famous camo sequence.

 

DWhatley

Kraken
Staff member
Moderator
Joined
Sep 4, 2006
Messages
20,698
Reaction score
1,833
Location
Gainesville, GA
The effect of predatory presence on the temporal organization of activity in Octopus vulgaris
Daniela V. Meisel, Michael Kuba, Ruth A. Byrne,Jennifer Mather - 2013 full article


Abstract

Studies of the daily activity patterns of Octopus vulgaris have shown varying activity in different habitats. This might stem from the octopus' ability to respond to influences such as predation pressure by adjusting its activity pattern. To test the hypothesis that a predatory threat could alter activity cycles, six octopuses were each held in a partitioned tank with a potential predator for a week. After we had determined the circadian activity of each undisturbed subject for two days, a nocturnal (moray eel, Muraena helena) and a diurnal fish (triggerfish, Balistes carolinensis) were alternately introduced into the second compartment of the tank for seven days. Each of these periods was then followed by a four-day period without eel or triggerfish. During the experiment, subjects had visual and chemical access but no physical contact. Octopuses showed an increase in activity in the presence of both species, but this increase was only significantly negatively correlated with the activity of the triggerfish. Attacks on the barrier by the octopus and the triggerfish decreased throughout the week, but this was not true for the octopus and the moray eel. We concluded that O. vulgaris can use temporal spacing of activity to respond to potential predators. This ability might be responsible for conflicting reports of activity patterns of O. vulgaris.
This is of particular note to keepers and the observed period of activity of O. vulgaris:

O. vulgaris, a generalist species (Hanlon and Messenger, 1996), it might be among those animals that show plasticity in their circadian rhythms and are thus able to switch their activity phase (Meisel et al., 2006).
In field studies O. vulgaris was found to be nocturnal in the Mediterranean ( Altman, 1966, Kayes, 1974 and Woods, 1965), but diurnal ( Hanlon, 1988 and Hochberg and Couch, 1971) in the Atlantic, even showing crepuscular peaks (Mather, 1988). One might argue that this could be due to population differences, but Mediterranean animals held in the laboratory actually showed diurnal ( Meisel et al., 2003 and Meisel et al., 2006) or variable peaks of activity (Wells et al., 1983). Octopuses often rely on speculative foraging, using tactile and chemical, rather than visual cues. Although Mather (1988) was unable to time octopus activity to daylight, tidal level or tidal flow, light has some – albeit, probably not an exclusive – function as a zeitgeber for O. vulgaris (Meisel et al., 2006).
While most animals are either classified as nocturnal or diurnal (Dunlap et al., 2004) O. vulgaris is apparently able to function equally well at both times of day, and therefore possesses the ability to switch between them.
 

DWhatley

Kraken
Staff member
Moderator
Joined
Sep 4, 2006
Messages
20,698
Reaction score
1,833
Location
Gainesville, GA
In spite of the literature, I have come to believe it is species dependent. When you see video of any of the animals with long webbing you will note that they envelope rock or pieces of coral and then explore with their arms or suckers to find food. All of our O. briareus and my current O. vulgaris (I think, a recent paper has me confused on what has been labeled Caribbean vulgaris and the attributes of O. burryi. This paper would make Margay O. burryi but Norman and many others - including the video at the top of this thread - note the patterning as O. vulgaris) have been extremely far sighted and can see very little close up. Margay often gets spooked when she realizes our hands are close by so we have to move our fingers to let her know proximity. The O. hummelincki I have kept seem to see much more sharply and have appeared to recognize different people as well as to hunt visually. They lack the extreme webbing of the other two and this may be a clue for visual acuity.
 

DWhatley

Kraken
Staff member
Moderator
Joined
Sep 4, 2006
Messages
20,698
Reaction score
1,833
Location
Gainesville, GA
[h=5]Phylogeographical Features of Octopus vulgaris and Octopus insularis in the Southeastern Atlantic Based on the Analysis of Mitochondrial Markers[/h] João Bráullio De Luna Sales, Péricles Sena Do Rego , Alexandre Wagner S. Hildorf , Angela A. Moreira , Manuel Haimovici , Acácio R. Tomás , Bruno B. Batista , Reynaldo A. Marinho , Unai Markaida ,Horacio Schneider. and Iracilda Sampaio

Subscription to BioOne required for full article
[h=3]ABSTRACT[/h] The genus Octopus occurs in tropical and temperate oceanic waters throughout the world, and currently includes 112 species, although the phylogenetic relationships among the different taxa are still poorly understood. The cosmopolitan Octopus vulgaris is one of the most widely analyzed cephalopods in genetic studies, primarily because of its ample range and the problems associated with the morphological identification of specimens, which indicate the possible existence of a species complex with a worldwide distribution. Two large-bodied octopus species—O. vulgaris and Octopus insularis—are found in the western South Atlantic. The limits of the geographical range of the O. insularis are still unclear. The current study is based on a phylogeographic analysis of the 2 species in the South Atlantic, with the objective of confirming their monophyletic status and the limits of their geographical distribution in this region. The analyses were based on the mitochondrial genes 16S rDNA and Cytochrome Oxidase subunit I (COI). The topologies generated for both genes confirmed the monophyletíc status of the 2 species. In the case of O. vulgaris, it was possible to confirm the monophyletic status of the specimens from this region relative to those of other areas around the world, although 3 distinct haplogroups were clearly differentiated, corresponding to the Americas, Europe and Africa, and Asia. The differentiation among these 3 groups may be determined by the limitations of the dispersal of paralarvae among continents. Further studies are needed to confirm the possible occurrence of distinct groups in the western South Atlantic, as well as the influence of oceanic currents on the phylogeographical distribution of O. vulgaris on the Brazilian coast
 

DWhatley

Kraken
Staff member
Moderator
Joined
Sep 4, 2006
Messages
20,698
Reaction score
1,833
Location
Gainesville, GA
Behavioural observations of the common octopus Octopus vulgaris in Baía dos Tigres, southern Angola
CL de Beer, WM Potts 2013 (subscription)

Abstract
Observations on the behaviour of the common octopus Octopus vulgaris were made during daytime and night-time sampling on an unexploited rocky reef habitat in Baía dos Tigres, southern Angola. The relative numerical abundance sampled was 0.47 octopus person–1 h–1during the day and 5.33 octopus person–1 h–1 during the night, suggesting that the population under study was nocturnal. The activity patterns differed between sizes of octopus. Small octopus (<20 cm total length [TL]) were observed roaming during the night, whereas the large individuals (>20 cm TL) generally fed in their dens. This ontogenetic behavioural shift may be due to tidal constraints or could be a strategy to avoid cannibalism. Octopus inhabiting a shallow, small-boulder substratum made extensive modifications to their habitat, excavating dens of up to 1 m deep in the sand below the boulders. These dens were not visible during the day as the octopus appeared to retract the small boulders over their den entrances. This unique behavioural strategy is thought to be a means to reduce predation and reduce light intensity during the day. Octopus were not observed in the small-boulder habitat during the five hours of daytime sampling. With nocturnal activity and extensive habitat modification, it is likely that avoidance of predation may be an important driver influencing the behaviour of the octopus population under study.
 

DWhatley

Kraken
Staff member
Moderator
Joined
Sep 4, 2006
Messages
20,698
Reaction score
1,833
Location
Gainesville, GA
THE HEARTBEAT OF OCTOPUS VULGARIS
M. J. WELLS 1978 (pdf)

SUMMARY
Heartbeat frequencies and blood pressures were monitored in freemoving
Octopus vulgaris. Typical resting frequencies (for animals of 500 g ±
at 22° C) were 40-50 beats min"1, with resting pressures measured at the
dorsal aorta of 40 cm H20 in systole and 15 cm in diastole, rising to 100 cm
or more with a pulse of 50 cm in exercise. Beat frequency changes very little
and any increased oxygen demand results mainly in an increase in stroke
volume. Temperature affects heartbeat frequency with a Qio of about 3 over
the range 7-27 °C. Systemic heartbeat rate and pulse amplitude also
change with the oxygen content of the water, slowing as this decreases and
stopping,
 

DWhatley

Kraken
Staff member
Moderator
Joined
Sep 4, 2006
Messages
20,698
Reaction score
1,833
Location
Gainesville, GA
An integration of historical records and genetic data to the assessment of global distribution and population structure in Octopus vulgaris
Daniele De Luca, GAETANO CATANESE, Gabriele Procaccini and Graziano Fiorito

The common octopus (Octopus vulgaris Cuvier, 1797) is one of the most widely distributed species belonging to the genus Octopus as well as an important commercially harvested species and a model organism for behavioral biology of invertebrates. It has been described for the first time in the Mediterranean Sea but it is considered a cosmopolitan species inhabiting the temperate and tropical sea of the northern and southern hemispheres. In the last few years, several species previously considered as O. vulgaris have been recognized as new species, limiting the distributional range of “vulgaris” and reinforcing the thesis of a species complex. Where it is an important fishery resource, numerous studies have been conducted in order to define its genetic structure with the purpose of managing different stocks. However, many locations are still poorly investigated from this point of view and others are under taxonomic revision to exclude or confirm its occurrence. Here we provide a summary of the current status of knowledge on distribution and genetic structure in this species in the different oceanic regions.
 

Latest Posts

Forum statistics

Threads
20,247
Messages
204,578
Members
8,462
Latest member
Arinabrits

Monty Awards

TONMOCON IV (2011): Terri
TONMOCON V (2013): Jean
TONMOCON VI (2015): Taollan
TONMOCON VII (2018): ekocak

Top