The blobfish, widely recognized for its unusual appearance, is often misunderstood. The familiar image of a gelatinous, sagging fish is not how it truly appears in its natural environment. This deep-sea inhabitant, scientifically known as Psychrolutes marcidus, lives in conditions vastly different from the surface, profoundly influencing its form.
Appearance in its Natural Habitat
In its deep-sea habitat, the blobfish does not resemble the shapeless mass commonly seen in photographs. Instead, it maintains a more typical fish-like appearance under immense pressure, with a large, rounded head that tapers into a tail, giving it a somewhat tadpole-like shape.
The blobfish measures less than 30 centimeters and weighs under 2 kilograms. Its skin is loosely attached, appearing soft and sometimes described as slightly spiky, without scales. Coloration ranges from pinkish-grey to blue-grey. Its features include pronounced black eyes, feathery pectoral fins, and a prominent mouth that can take up a significant portion of its head.
Adaptations for Deep-Sea Life
The blobfish thrives in the extreme conditions of the deep ocean, found at depths between 600 and 1,200 meters (2,000 to 3,900 feet) off Australia, Tasmania, and New Zealand. Here, water pressure can be 60 to 120 times greater than at sea level, and its body composition is adapted to withstand this crushing pressure.
The blobfish has a soft, gelatinous body with a density slightly less than water, allowing it to float just above the seafloor without expending much energy. This is an advantage in an environment with scarce food resources. Unlike most fish, it lacks a swim bladder, an air-filled organ that would implode under the extreme pressure of its habitat. Its skeleton is minimal, composed of soft bones that would otherwise be crushed at these depths.
Why it Changes Shape
The change in the blobfish’s appearance when brought to the surface is a direct result of the drastic pressure difference. Its “blob-like” form is not its natural state but an artifact of decompression damage. When rapidly pulled from its deep-sea home to sea level, the immense external pressure that supports its body is suddenly removed.
Without high pressure to maintain its structure, the blobfish’s gelatinous tissues expand and lose integrity. This causes its body to collapse into the recognizable, shapeless mass. The soft bones and lack of muscle cannot provide necessary support in a low-pressure environment. Gases dissolved within its tissues can also expand, similar to decompression sickness in humans, contributing to its altered appearance.