Hide and seek in the open sea: pelagic camouflage and visual countermeasures.

@article{Johnsen2014HideAS,
  title={Hide and seek in the open sea: pelagic camouflage and visual countermeasures.},
  author={S{\"o}nke Johnsen},
  journal={Annual review of marine science},
  year={2014},
  volume={6},
  pages={
          369-92
        }
}
  • S. Johnsen
  • Published 3 January 2014
  • Art
  • Annual review of marine science
Camouflage is exceptionally challenging in pelagic environments because of their featureless nature. Thus, it is perhaps no surprise that pelagic species have evolved highly sophisticated cryptic strategies, three of which-transparency, mirrors, and counter illumination-are rare or absent in other habitats. Pelagic visual systems are equally complex, and several visual capabilities, including UV and polarization sensitivity and intraocular filters, are thought to facilitate detection of… 

Figures from this paper

Ultra-black Camouflage in Deep-Sea Fishes

Open-ocean fish reveal an omnidirectional solution to camouflage in polarized environments

Disappearing act Unlike coastal regions and reefs, the open ocean is mostly empty. Many fish species, nonetheless, spend most of their lives there. Such emptiness makes camouflage exceedingly

Transparency, a better camouflage than crypsis in cryptically coloured moths

This work monitored and compared survival of a fully opaque grey artificial form (cryptic), a form including transparent windows and a wingless artificial butterfly body, suggesting a reduction of detectability conferred by transparency, the first evidence that transparency decreases detectability in cryptic terrestrial prey.

Evidence that eye-facing photophores serve as a reference for counterillumination in an order of deep-sea fishes

It is found that all sampled species with ventral photophores capable of counterillumination possess an eye-facing photophore that is pigmented on the anterior and lateral sides, thus preventing its use as a laterally directed signal, lure or searchlight.

Computational visual ecology in the pelagic realm

A computational approach to investigate visual ecology in the pelagic realm using information on eye size, key retinal properties, optical properties of the water and radiance, and expressions for calculating the visual range for detection of important types of pelagic targets are developed.

Not as clear as it may appear: Challenges associated with transparent camouflage in the ocean.

  • Laura E Bagge
  • Environmental Science
    Integrative and comparative biology
  • 2019
This review summarizes several recent discoveries of multiple unique adaptations for minimizing light scattering both on the exterior cuticle surface and throughout the body volume of transparent crustaceans, as well as the potential tradeoffs and challenges associated with transparent camouflage.

Open water camouflage via ‘leaky’ light guides in the midwater squid Galiteuthis

Variation in the geometry of the photophore light guides reproduces the predicted variation in ocean radiance experienced by Galiteuthis, a midwater squid, and may reproduce the angular distribution of light at all positions in its habitat.

Photon Hunting in the Twilight Zone: Visual Features of Mesopelagic Bioluminescent Sharks

Comparisons with previously published data reveal ocular differences between bioluminescent and non-bioluminecent deep-sea sharks, and biolumerinescent sharks possess higher rod densities, which might provide them with improved temporal resolution particularly useful for biolUMinescent communication during social interactions.

Transparency reduces predator detection in chemically protected clearwing butterflies

It is demonstrated for the first time that transparency on land likely decreases detectability by visual predators, and humans could learn to better detect the most transparent species over time.

Transparency reduces predator detection in mimetic clearwing butterflies

It is demonstrated for the first time that transparency on land likely decreases detectability by visual predators, and humans were able to learn to better detect the more transparent species over time.
...

References

SHOWING 1-10 OF 69 REFERENCES

Propagation and Perception of Bioluminescence: Factors Affecting Counterillumination as a Cryptic Strategy

The appearance of the counterillumination was more affected by the visual acuity of the viewer than by the clarity of the water, even at relatively large distances, which has implications for the study of spatial resolution, contrast sensitivity, and color discrimination in deep-sea visual systems.

Cryptic coloration and mirrored sides as camouflage strategies in near‐surface pelagic habitats: Implications for foraging and predator avoidance

Mirrored and colored surfaces are common adaptations for crypsis in pelagic habitats. Although highly successful when optimized for a particular situation, either may become less successful if it is

Mesopelagic Cephalopods Switch between Transparency and Pigmentation to Optimize Camouflage in the Deep

Cryptic and conspicuous coloration in the pelagic environment

  • S. Johnsen
  • Environmental Science
    Proceedings of the Royal Society of London. Series B: Biological Sciences
  • 2002
The underwater radiance distribution in tropical oceanic water was modelled using measured inherent optical properties and radiative transfer calculations to predict the reflectance spectra that resulted in minimal or maximal object contrast as a function of depth, viewing angle, azimuth and solar elevation, showing that red coloration is most cryptic at depth.

Crypsis in the Pelagic Environment

Special attention is given to transparency as the most prevalent, yet least understood, of these mechanisms that are used in predator-prey interactions, and particular emphasis is placed on light as a determinant of effective modes of crypsis in the two different habitats.

Concealment in epipelagic pterotracheid heteropods (Gastropoda) and cranchiid squids (Cephalopoda)

In cranchiids, tilting of the organs alone suffices and adjustments are accomplished much more rapidly than in the pterotracheids, and these two groups have achieved convergent solutions to this problem.

Polarization sensitivity as a contrast enhancer in pelagic predators: lessons from in situ polarization imaging of transparent zooplankton

It is shown that relatively simple algorithms can use this negative polarization contrast to increase visibility substantially and is most likely due to the low radiance of the horizontal background light when compared with the downwelling irradiance.

Sun-compass orientation in the characidCheirodon pulcher

SynopsisSmall microcharacidsCheirodon pulcher were netted during the dry season in pools of the savanna ‘llanos’ at a considerable distance from the main river channel. Fish could have moved from the

Does new technology inspire new directions? Examples drawn from pelagic visual ecology.

  • S. Johnsen
  • Environmental Science
    Integrative and comparative biology
  • 2007
A renaissance may be developing in the study of the integrative biology of pelagic species by using spectrometers, microspectrophotometery, electroretinography, and ultraviolet and polarization imaging systems to test long-standing hypotheses in pelagic ecology.

The Red and the Black: Bioluminescence and the Color of Animals in the Deep Sea1

  • S. Johnsen
  • Environmental Science
    Integrative and comparative biology
  • 2005
Estimates of the contrast sensitivity of deep-sea visual systems suggest that even approximate matches may be sufficient for crypsis in visually complex benthic habitats.
...