While some marine animals spend most of their lives in or near the exact same spot, there are some creatures that prefer to use different sites for hibernating, mating, brooding, and other activities. These sites often vary in terms of temperature, depth, and overall environment, and they are often located long distances from one another. Despite this, these creatures are able to make their way easily from one site to the next. So what gives these creatures their sense of direction? How do they make their way from one place to the next? Here, we take a closer look at how many different types of marine animals navigate through the underwater environments they call home.
Sensory Input, Echolocation, and the Earth’s Magnetic Field aid Navigation
Many marine animals are equipped with well-developed senses, and many are able to detect the earth’s magnetic field. Using combined methods, these creatures have the uncanny ability to travel long distances despite current, changing underwater landscapes, and other confusing factors.
Most of these animals rely heavily upon sensory input, with whales and dolphins being among the best navigators. These cetaceans emit low-frequency sounds via specially designed nasal cavities. The sound waves they produce travel long distances underwater, echoing back toward the animals when an object is encountered. The animals then decode the echoes, accurately determining the direction and distance of an object, as well as their distance from that object.
This process is known as echolocation – and not only can whales, porpoises, and dolphins recognize proximity to an object or another creature, they are also able to distinguish between obstructions, targets, and enemies. Echolocation is used for hunting and for communicating, as well as for navigating. There are a few unfortunate cetacean species which are unable to use echolocation; these animals are much more likely to suffer from collisions with boats and from entanglement in nets.
Not only do cetaceans utilize echolocation to hunt and to identify various objects in the water surrounding them, they often use this skill to communicate with members of their own species as well as with other cetaceans. In many cases, certain whales and dolphins use their echolocation abilities to communicate with one another across large distances. Most species with this capability are able to detect and receive a wide range of frequencies, but as a rule, all are most sensitive to the frequencies at which echolocation takes place.
These facts don’t explain how marine life navigates using the earth’s magnetic field, and science is not able to explain exactly how these animals manage to make their way through the oceans using magnetic fields, either; however, there are some interesting theories that could prove to explain this phenomenal ability.
The earth’s magnetic fields vary from one place to the next, and scientists theorize that marine animals are able to analyze both the direction and the intensity of these fields, using direction finding abilities which have been likened to the inner workings of a magnetic compass. In short, it is believed that many marine species are able to analyze the earth’s magnetic energy in an exacting way which enables them to navigate underwater.
Turtles, for example, are known to have the capacity to pick up specific magnetic fields that are spread over various parts of the oceans. The turtles respond to magnetic fields at certain locations; then they turn in certain directions in order to orient themselves toward their desired destinations. These locations are like guiding stars to the turtles, who have spent millennia honing their instincts.
Another interesting fact about turtles’ ability to navigate is that mature turtles have strong attachments to their breeding grounds. Their inner compasses tell them whether to the north, south, east, or west of their preferred mating areas; once they have determined their positions, they are able to automatically point themselves toward their destinations.
Turtles are not the only marine animals with highly developed navigational skills. Sharks, certain fishes, lobsters, and many cetacean species are also capable of using the earth’s magnetic fields to orient themselves within their environments and navigate accordingly. Many of these animals have special receptors located in the area near the eyes and nose; these receptors are believed to work in concert with sight and smell.
Lobsters have amazed scientists with their ability to navigate; after all, these animals have simple nervous systems. These crustaceans have the ability to map the areas they inhabit, creating preferred pathways using directional guidance from the earth’s magnetic field to stay on track. When compared with other simple creatures without this ability, such as nudibranchs, it’s easy to see how well lobsters are able to use their navigational abilities to make their way through the underwater world, even though the water they inhabit is often murky.
Electricity Plays a Role
Many animals are able to detect electricity; we humans often feel a tingling sensation when we are near an electric field, for example. Sharks, rays, and some other marine animals are even more in tune with electric fields than we are, and are capable to use special electroreceptors in concert with the earth’s magnetic lines, plus their senses of sight and smell, to make their way through even the murkiest water with precise accuracy. Besides using these capabilities for navigating from one place to the next, these animals use their electroreceptors to detect prey and other food items in a stunningly sophisticated manner.
Following Their Noses
Some marine animals have noses so sensitive that they can detect odors emanating from objects as far as 1,000 kilometers away. This amazing capability is quite puzzling and is not completely understood; scientists continue to determine exactly how scents travel through water for such long distances, and to determine exactly which odors compel these animals to head in certain directions.
Without a doubt, learning more about how animals navigate, as well as gaining insight about their habits, helps us to determine which animals we might encounter while diving. It also provides us with the ability to predict behavior to a certain degree, enabling us to enjoy wildlife encounters more than ever.