Role of vision in behavior, visual field, and visual acuity of cuttlefish Sepia esculenta

Abstract

SUMMARY : The role of vision in the entry of the cuttlefish Sepia esculenta into basket traps was examined in laboratory experiments and by histological examination of the retina. Both entry into the trap and feeding on shore crabs stopped when the tank was completely darkened. The eyes of cuttlefish have a high sensitivity to light. The visual field of cuttlefish was determined by the optical method, based on the assumption that incident light on the pupil from any direction reaches the retina through a refractive lens. The uniocular visual field was found to be 253° on the horizontal plane, and the anterior and posterior binocular visual fields were 86° and 60° respectively. On the retina, areas with especially high visual cell density formed a visual equator slightly above the optical equator. The distribution of the visual cell density indicates no specific visual axis. The visual acuity is 0.36 when estimated from the bait recognition distance and the size of bait during feeding, and 0.89 when determined from the visual cell density at the visual equator and the focal length of the lens. Cuttlefish have far superior visual acuity than fish.

Disruptive Body Patterning of Cuttlefish (Sepia officinalis) Requires Visual Information Regarding Edges and Contrast of Objects in Natural Substrate Backgrounds

“…The result, that animals responded differently on the original digital photograph of gravel and the blurred picture of gravel, supports the notion that the cuttlefish visual system has good spatial resolution (16), and that the details of the scene (e.g., the edges of objects) are important for cuttlefish to produce appropriate camouflage patterns. Ver-tebrate visual systems tend to use edge detection to recognize an object.…”

Turning performance of brief squidLolliguncula brevisduring attacks on shrimp and fish

“…This result indicates that squid are very effective predators, irrespective of the prey target. This does not come as a surprise given their unique ability to swim readily in multiple orientations (Bartol et al, 2001a(Bartol et al, ,b, 2016, their high maneuverability and agility , their capacity to rapidly extend their tentacles and manipulate their muscular arms (Kier and Van Leeuwen, 1997) and their high visual acuity (McCormick and Cohen, 2012;Watanuki et al, 2000).…”

Night vision by cuttlefish enables changeable camouflage

“…Because they assess their visual environment and continue to camouflage in very dim light, we can speculate that these animals might use this behaviour (1) to avoid predators with keen night vision and (2) to increase their own hunting success at night (cuttlefish are carnivorous predators). In particular, S. officinalis has been suggested to be active day and night (Denton and Gilpin-Brown, 1961;Mark et al, 2007;Watanuki et al, 2000). For other species that are less active at night, such as S. apama (Aitken and O'Dor, 2005), it is likely that nocturnal camouflage behaviour is an anti-predator tactic .…”

“…All reproductive signalling behaviour ceases at night and is replaced by camouflage to avoid detection by predators . Sepia officinalis, by contrast, has been reported to be cathemeral, active both day and night (Watanuki et al, 2000); some of their physiological processes undergo diurnal cycles, suggesting that physical activity might be increased at night (Denton and Gilpin-Brown, 1961;Mark et al, 2007). Irrespective of diurnal activity changes, cuttlefish night vision must be well developed (either to detect prey or to avoid becoming prey), and we might therefore expect their camouflage body patterns to be fine tuned and changeable, even at night.…”