This week we’re switching up our Wisdom Wednesday blog to be more of an update about a popular topic in ocean pollution: Sea Turtles. Sea turtles are affected by plastic during every stage of their life. They crawl through plastic on the way to the ocean as hatchlings, swim through it while migrating, confuse it for jellyfish (one of their favorite foods), and then crawl back through it as adults. Researchers estimate that over half of all sea turtles in the world have ingested plastic. And a single piece of plastic has a 20% chance of killing them. If sea turtles disappear from the ocean, it wouldn’t only be a huge loss for future human generations but it would also threaten the longevity of other marine life. Scientists believe that sea turtle species are essential to the health of marine ecosystems.
The hatchlings do not have sex chromosomes so their gender is determined by the temperature within the nest. The temperature varies slightly among species, ranging between roughly 83-85 degrees Fahrenheit (28-29 degrees Celsius), at which embryos within a nest develop into a mix of males and females. Temperatures above this range produce females and colder temperatures produce males. It's estimated that only 1 in 1,000 hatchlings will survive to adulthood. Once near the surface, they will often remain there until the temperature of the sand cools, usually indicating nighttime, when they are less likely to be eaten by predators or overheat. Once out of the nest, hatchlings face many predators including ghost crabs, birds, raccoons, dogs, and fish.
In addition to their possible great size, another defense that some groupers have is the ability to change the color of their skin to match their background.. Sometimes this color change is simple, such as turning from dark to light in order to blend in with varying levels of light. They swim slowly, but with power. They're not capable of fast breaks or swimming long distances, but anyone who's been on the other end of one on a deep sea fishing charter in Destin can tell you they have one heck of a dive pull. Some groupers are so huge that when they open their mouths to feed, they create a suction that is powerful enough to inhale small prey.
Whale sharks are filter feeders that eat plankton through their gills for much of their nourishment. They also eat squid, krill, and small fish. A whale shark can process more than 6,000 liters of water an hour through its gills. Whale sharks are in no way related to whales. Although they are sharks, they are very docile. A whale shark’s mouth is at the very front of its head—as opposed to the underside of the head like most sharks.
Terns are a common seabird that frequently get mistaken for seagulls. These graceful birds are characterised by their silver-grey upperparts, white underparts, black cap and red bill, as well as long tails. Almost all terns migrate, and the Arctic tern migrates every year from the Arctic to the Antarctica –a 25,000 mile trip, one way! Common tern colonies usually number around 2,000 birds, but can be as large as 20,000. They are often shared with other tern species such as Arctic and roseate terns.
Humpback Whales are known to be one of the most playful and acrobatic whales on earth. Of all cetaceans, the Humpback Whale seems to be the most athletic, impressing observers with breaching, spy hopping and other playful behaviours. They can be seen laying on their side "pec slapping", raising their large pectoral fins straight out of the water and slapping it hard against the surface. They are often seen swimming like this, passing vessels close by, but ignoring them.
Tasmanian Blenny fish are odd looking fish that bring joy to the reefs with a large head, a blunt snout with a steep profile, and a large frilled tentacle over each eye. Tasmanian Blennies are pale brownish to dark brown or bluish-grey with a pattern of irregular bars and blotches on the sides, and two dark bars radiating from below the eye.
Algal blooms are one common source of thick sea foams. When large blooms of algae decay offshore, great amounts of decaying algal matter often wash ashore. Foam forms as this organic matter is churned up by the surf. Most sea foam is not harmful to humans and is often an indication of a productive ocean ecosystem. But when large harmful algal blooms decay near shore, there are potential for impacts to human health and the environment.
This extraordinary invertebrate has a mass of twisting and turning arms that can measure a meter long. The middle is a five-pointed body that’s up to a few inches across. An arm extends from each point. Each arm may have two main branches, with many smaller ones extending from each of the bigger ones. Each branch has tiny sharp hooks, allowing the creature to capture prey.
Pineapple fish have very unusual feeding habits. They have thin, tiny teeth and feed at night with a small green patch on their lower jaw that is covered in small bacteria that glow in the dark. This glow attracts small shrimp. This patch turns from green to red as they get older.
The horseshoe crab is a living fossil. It has been on Earth some 220 million years, longer than dinosaurs. And it survives today almost identical to its ancient ancestors. Horseshoe crabs are more closely related to spiders, ticks and scorpions than they are to true crabs.
The females taking care of their fry are called maternal mouthbrooders because the female immediately picks up the fertilized eggs and holds them in her mouth for about three weeks while the little ones hatch and grow a bit. During this time, the female will not eat in order to give the next generation a head start in life.