Our first encounter with a dusky shark (Carcharhinus obscurus) occurred in South Africa in the waters just outside of Port St. Johns. We were there nine days to photograph the famous sardine run. As sharks take part in devouring the bait balls of fish created by the common dolphin we were hoping to photograph the dusky shark as well as spinner shark for the first time.
Unfortunately, we did not photograph a dusky during the fish bait ball event as they were largely spinner sharks involved. However, we did have one encounter with a dusky near the chase boat. We got in the water and captured a few shots of this new species of shark for us. It is always exciting to see and photograph a new species of shark for the first time.
The sardine run of South Africa occurs between June and July on most years. Millions of sardines (Sardinops sagax) attract thousands of predators including dolphins, tuna, sharks, whales, and birds. It also attracts people who wish to see and photograph this spectacular event.
The long-beaked common dolphins (Delphinus capensis) are the driving force that creates the fish “bait ball”. Large pods of dolphins work cooperatively to herd the fish into these tight groups. Sardines along with mackerel (Scomber japonicus) group together when they are threatened. The dolphins force the fish up to the surface where they are easier to catch.
After the dolphins have done the hard work many other predators begin to take advantage of such a large concentration of fish. The Cape gannets (Morus capensis) are large seabirds that begin to dive by the hundreds into the fish bait ball. They reach speeds of over 100 km/h (60 mph) as they hit the water. If not initially successful they will chase the fish underwater hoping for a meal.
Not to miss out sharks begin to show up in large numbers. Spinner sharks (Carcharhinus brevipinna) were the most common on our encounters although there were also bronze whaler sharks (Carcharhinus brachyurous) called copper sharks in South Africa and dusky sharks (Carcharhinus obscurus).
Each year can be very different. We had very poor visibility (10 feet or 3 metres) on our first 8 days and few bait balls. We did not see a single sardine in our 9 days on the water. Fortunately, we encountered a fairly large bait ball of mackerel on our final day in a pocket of water with relatively clear visibility that allowed us time to get in the ocean. This 20-30 minute event produced all of these pictures.
As we shark dive around the world we rarely have an opportunity to visit a shark research facility. Our two weeks on Bimini Island allowed us to photograph great hammerhead sharks, bull sharks, nurse sharks, blacknose sharks, Caribbean reef sharks, southern stingrays, and Atlantic spotted dolphins. What a fantastic diversity of big animals around a very small island. We got to see baby lemon sharks and nurse sharks at the Bimini Shark Lab.
The research they do here is invaluable. Sharks are under threat worldwide and research is needed to better understand them and protect their nursing sites. One thing that their research has revealed is that the female lemon shark returns to the same mangrove sites that they were born at to give birth to their pups. Knowing this allows researchers to influence governments to protect these critical environments.
We found it fascinating to go to their holding pen to see the young shark pups that they were doing research on. We photograph the adults in the oceans but never see pups. Young sharks reside in the mangroves skirting the islands for protection in their early years but at some point venture away from these safe zones. The shark pup with the barbels is a nurse shark and the other is a lemon shark. So neat to see such young, small sharks.
Bimini Island in the Bahamas is where these photographs were taken. It is a small island 80 km (50 miles) from the Florida coast and has a large variety of shark species. On this trip, we also encountered great hammerheads, nurse, blacknose, blacktip, and bull sharks. They are commonly found in shallow water around coral reefs.
Caribbean reef sharks (Carcharhinus perezii) are the most common requiem shark species encountered by divers in the Caribbean sea. They also inhabit parts of the Western Atlantic ocean. If you dive in the Caribbean you may encounter this shark as it is relatively common.
Most of the baited shark dives involve the Caribbean reef shark. This is often the first “shark dive” new divers will take part in and it can be thrilling. We did this years ago with our kids and I must say we were nervous and our adrenaline was sure flowing. However, this made us fall in love with sharks when we realized just how majestic they were. This surreal experience led us to pursue our “shark hobby” and we have been photographing them ever since.
They average about 1.5 to 2 meters (5-7 feet) in length but can reach lengths of about 3 meters (9 feet). They often hang out around Caribbean reefs and it is likely the largest shark you will encounter while reef diving. Their diet consists of a variety of fish, octopus and small rays.
Caribbean reef sharks can evert their stomachs which means the stomach is turned inside out. This is helpful to discard undigested food and plastic. Unfortunately, our oceans are now full of discarded plastic from human consumption. These plastics are often ingested by marine organisms and are responsible for many needless deaths.
Okay, I’ll say it. I grew up watching Bugs Bunny as a kid and loved the cartoons with the roadrunner (Geococcyx californianus) and that bumbling Wile E. Coyote who tried endlessly to capture that speedy bird. I must say that I admired the coyote. He was a persistent fellow and never let failure deter him.
Up until last year, I had never observed a roadrunner and it was different than I expected (too many cartoons). It is in the cuckoo family living in open arid habitats in northern Mexico and in the southwestern United States.
The roadrunner is capable of flight but prefers the ground. We were able to photograph it in a tree which is apparently not common. As you can see, all of our ground pictures are still shots. I did not anticipate the speed of this bird, which can reach speeds of 30 km/h (20 mph). Wildlife encounters are often brief. I had my shutter speed at 1/200 of a second which proved much to slow for a speedster like a roadrunner.
The roadrunner nests in cactus or a thick shrub not far off the ground and will lay 3-5 eggs. These eggs will hatch in about 20 days and the chicks will be capable of running in another 18 days.
Because it lives in an arid environment the diet includes a wide variety of desert organisms including snakes, lizards, scorpions, spiders, and insects. An adult bird is capable of killing rodents and small birds. It can be seen holding larger prey in its bill and smashing it into the ground repeatedly until its victim dies.
Scuba diving in the dark is always an adrenaline rush because you know that there are sharks near you but you can’t see them until they suddenly appear. We love night dives because they add an entirely new dimension to exploring the underwater world. We photographed these great hammerhead sharks around Bimini Island in the Bahamas.
Sharks are very comfortable swimming in the water at night. To simplify, their eyes are designed to allow light to pass through the retina twice which enables sharks to see in the dark. It is believed that sharks can see about ten times greater than humans in clear water.
They also have a cephalofoil (the hammer) that is full of electrical sensors. These electroreceptors are interconnected jelly-filled pores called ampullae of Lorenzini and aid in hunting as these sensors pick up electrical signals given off by all living creatures including humans. Therefore, a shark at night is very aware of your presence and location in the ocean even though you have no idea where they are.
Another freshwater turtle we found in the Las Vegas wetlands was the Red-Eared Slider turtle (Trachemys scripta elegans). This turtle is not native to this area. It is bought as a pet but as with many pet owners, they irresponsibly release it into the wild when they don’t want it anymore. We counted as many as 15 turtles in this pond. The danger is that invasive species may out-compete native turtle species causing a decline or eradication of the native Spiny Softshell turtle.
When water temperatures drop below 10 degrees Celcius (50F) turtles are generally not active but brumate. Brumate is a form of hibernation. They will sleep on the bottom of the pond, awaken, swim to the surface, possibly drink water and then proceed back to the bottom. The process repeats itself periodically. During brumation, they do not eat.
Las Vegas had a cold spell with temperatures around freezing at night. There was some snow which is unusual here. This is why we were surprised to see these turtles sunning themselves on the rocks in the early morning. These turtles should not have been as active as they were considering the weather conditions.
Red-Eared Slider turtles can live for 20-30 years. The shell (carapace) averages between 15cm (6 inches) and 30cm (12 inches) in length. Females generally are larger than the males. A large female can lay up to 30 eggs and may lay up to 5 times (clutches) in a year.