By: Tim, Tony and Crystal Fish By: Tim, Tony and Crystal

Bony Fishes characteristics Bony fishes vary greatly in size. Extremely diverse and abundant group consist of over 28,000 species. 3 pairs of gill arches Ray-finned fish ex: clown fish Lobe-finned fish ex: Lungfish

Feeding There is a very diverse range of food preferences Some are herbivores, some carnivores and some omnivores As a group, bony fishes can eat all sizes of plants and animals, from microscopic plant plankton to come of the largest marine animals. Common diets include: Worms, marine snails, mussels, clams, squids, crustaceans, insects, birds, amphibians, small mammals and other fish Amount of food intake is directly related to size of fish and metabolic rate. Smaller fish have higher metabolic rate, thus smaller fish eat more Some fish are predators and hunt for their food, others can filter feed, which is straining plankton from the water in their gills

Reproduction Different fish become sexually mature at different ages, some are sexually mature at birth Most bony fishes mature after 1-5 years Reproduction is generally cyclic, cycles can be as short as 4 weeks and as long as years Many bony fishes spawn once a year until they die

Habitat Bony fishes inhabit almost every body of water They can live in freshwater, seawater, and Brackish (mixture of sea and freshwater) They can live in virtually all habitats: Rocky shores, coral reefs, kelp forests, rivers, streams, lakes, ponds Some fish live in open waters (Pelagic) ex: tunas Can live in various temperatures In general bony fish rely on dissolved oxygen in water for respiration. Some fish live in open waters (Pelagic)

Cartilaginous Fish: Sharks, stingrays and chimeras. Skeletons composed of cartilage. Sandpaper-like scaled called placoid scales. Two major groups: Holocephalans & elasmobranchs. 970 species. (Placoid scales under a microscope.)

Sharks: Amongst the top predators of the ocean. Most are carnivorous, meaning they eat other organisms such as marine mammals, fish and seabirds. Whale shark, megamouth shark and basking shark are zooplanktivorous. Prefer to inhabit waters less than 2000 meters in depth. SHARK ANATOMY- Tail – Caudal fin. Organ used to transfer sperm during reproduction is called a clasper. Ventral mouth filled with multiple rows of teeth. Teeth are constantly replaced, and sharks can use up to 30,000 teeth in their lifetime. Sharks are incapable of motioning their jaws back and forth to chew, so instead they swallow chunks of their prey whole.

Sharks (cont’d): HUMAN INTERACTION- Humans exploit shark populations for their fins, meat, oils, leather, cartilage and sport. Sharks are “finned” and then released back into the ocean to die a horrible death. (Attacked by other sharks or simply bleed to death.) Sharks are usually seen as threats; however, shark attacks are 47 times rarer than being struck by lightning. Out of all shark attacks, 8% are fatal.

Skates and Rays: DEFENSE MECHANISMS- HUMAN INTERACTION- Differ from sharks by having flatter bodies, greatly enlarged pectoral fins, reduced dorsal and caudal fins, eyes and spiracles on top of their head and gills slits are placed vertically. Most tend to live at the ocean floor. DEFENSE MECHANISMS- Electric rays have electric organs in their head that produce 200 volts. Stingrays have venom glands in their spine (tail) and it can cause severe pain or even death. Sawfish have pointed barbs along their snouts in which they shake their heads back and forth to attack if threatened. HUMAN INTERACTION- Both skates and rays are killed for food. Unlike sharks, skates and rays are not as protected by humans, meaning most of the species are threatened.

Skates and Rays (cont’d): DIFFERENCE BETWEEN SKATES AND RAYS- SKATES- Create a wave that they use to travel on against the ocean bottom. They have fleshier tails than rays. RAYS- Motion fins up and down. (Similar to how a bird uses its wings to fly.) Spine-like tails. (Tend to have venom glands equip with their tail.) Rays tend to grow much larger than skates. REPRODUCTION- Rays tend to give birth to live young, in contrast to skates, who release their eggs in a leathery, rectangular egg case called a mermaid’s purse.

Chimeras: CHIMERA ANATOMY- REPRODUCTION- HUMAN INTERACTION- Also known as the “ratfish”, “rabbitfish” and “spookfish”. CHIMERA ANATOMY- Uppers jaws are immovably attached to the braincase. Adults lack a spiracle. Gills are covered by a flap called an operculum. Instead of teeth, chimeras have flat plates they use to crush their prey. REPRODUCTION- Claspers on both the pelvic fins of males and on the head for reproduction. Chimeras produce large eggs in a leathery case. HUMAN INTERACTION- Marketed as food in parts of China and New Zealand. Their oils are known to be made into a fine lubricant. Similar to skates and rays, there is not as much protection for these species due to the fact only 33 species are known. (Rarely used commercially for this reason as well).

Jawless Fish Hagfish Only known animal to have a skull but no vertebral column Feeds by sucking on the blood of other fish Found in cold temperate waters Lampreys 38 known species of lampreys Average lifespan of 14 years Used as delicacy in european countries

Feeding Lampreys Eat shrimp, crabs and flesh of other animals They can go months without feeding Hagfish Feed by sucking the blood of other fish

Reproduction Both hagfish and lampreys use external fertilization. Females usually outnumber males by 100 to 1

Niche/Habitat Lampreys Spend 10 years in fresh water, then move to sea water for 2 years, then back to fresh water Hagfish Found in cold temperate waters. Usually at the sea floor.