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Presented by Kids Story Room A story podcast for young people Support pack for the Pod Play National Science Week 2020 Kids Story Room – http://kidsstoryroom.com
CONTENTS • Key learning areas/Themes/Synopsis • Thematic Activities • Comprehension and Discussion Questions • Cast of Ocean creatures: Blobfish/Tuna/Prawn/Leafy Sea-dragon/Swordfish • About Kids Story Room • Colouring In • Find–a-word • Weblinks and other Marine Education Resources • Ocean Zone Pull Through KEY LEARNING AREAS The Environment – marine habitat and fishing practices/South Australian marine species English/use of language and dialogue – character/personality types Respect for the elderly/working together as a team/overcoming challenges and looking after each other THEMES • The future of our marine life and how we can manage it sustainably • Marine ecosystems and ocean zones • Awareness of our surroundings • Positive consequences of our actions (relay teamwork) • Overcoming challenges and fears to achieve a goal • Empathy • Finding solutions to problems Kids Story Room – http://kidsstoryroom.com
CALL OF THE BLOBFISH – SYNOPSIS Deep down in the magical world beneath the waves, the wise and ancient Blobfish needs help. Blobfish reveals to his friend, Prawn, that trouble is on the way and Blobfish needs to speak to a human being, urgently. Prawn springs into action to save his wise old friend and swims up into the open waters of the big blue sea where he meets Swordfish. Swordfish joins the quest and in turn meets Tuna, who leads him to Leafy Seadragon, who sends them to Mera, the dolphin. Each one in this jumbly bunch of sea creatures must overcome their fears and work together in order to protect the Blobfish and save their ocean home. How will they get a person to the very bottom of the ocean? Can they overcome their differences and work as a team? What will they do to save the Blobfish? Kids Story Room – http://kidsstoryroom.com
THEMATIC ACTIVITIES • Check out the Sustainable Seafood Guide app – an initiative of the Australian Marine Conservation Society and designed to assist us humans to understand more about the seafood we consume. It’s an excellent resource to learn about what fish we can eat and what fish we should say No to for now. • The pod play Call of the Blobfish explores our marine environment and mentions the different ocean zones. Attached to this pack is a ‘pull-through’ that looks at the different zones of life in the ocean. Make the pull through and then add the creatures from the play to the zones where they live. • In Call of the Blobfish all of the characters help each other to succeed. The play is like a relay race to the finish line. Set up some relay activities in the classroom or playground where in groups of 5 or 6, the students each have a part to play in making something positive happen. (For example: planting a new tree or a herb one person carries the seed, another the water, another digs the hole, another covers the seed with earth and another puts a little stick in the ground to remember where they planted it. Then 5 people are responsible for the life of a little plant. Hopefully all of them will remember that it needs water every day!) • The play references the positive effects of marine parks, of looking after special species of fish and of letting some areas have a rest to replenish the stocks. Ask students to come up with examples of these sorts of ideas on the land. For example: what happens in a field after the cows eat all the grass…. What do farmers need to do to let the grass grow back? It’s the same for the ocean, we need to be careful not to fish too fast so that we can all enjoy seeing and eating fish into the future! • The Blobfish in the play is based on a real fish that lives in the twilight zone of the waters off South Australia and Tasmania. Show the students a picture of the Blobfish and ask them to write a story from his perspective, about what it is like to live so deep in the sea and the sorts of creatures who might live down there with him. • A fun way to remember the play so that different elements can be discussed: In groups of 3, let each student choose a different character and put together a ‘frozen statue’ moment from the play. Then ask the rest of the class to guess which moment in the play their ‘freeze frame’ is from. • Who was your favourite character? Draw a picture of the character and talk about why he or she was your favourite. • Call of the Blobfish is a creative piece of writing. Perhaps the students could do their own piece of creative writing from the perspective of one of the characters in the play. It could be presented as a monologue, an illustrated comic strip or a short story. • There are different sea creatures in the play and their characters are all different. Ask each student to secretly choose a creature and ask them to transform into their chosen creature without using their voices. The other students have to guess which creature they are pretending to be. • The play discusses the idea of how important elders are in our communities. Ask each student to share a story that might have been told to them by their grandparent or an older person they know. Kids Story Room – http://kidsstoryroom.com
COMPREHENSION AND DISCUSSION QUESTIONS/QUIZ v In what zone of the ocean does the Blobfish live? v Why was the Blobfish so important to all the other sea creatures? v Why was the Blobfish in danger? v All of the creatures in the play helped to save the Blobfish. What did they each do? Prawn? Swordfish? Tuna? Leafy-Sea? Dolphin? Sam? Fisherman? v What is a marine park and why are they important? What other areas of ocean near Australia need protection? There’s one very iconic protected area off the coast of Queensland! v Eating fish is an important part of our diet. What can we do to ensure there are lots of edible fish in the sea for many years to come? v How was the Blobfish going to be caught? Do you think anyone would want to eat him? v Why is it so important to respect and listen to our elders? v Swordfish has a sword to help him catch his food and look after himself. He started out wanting to use it to fight. What did he learn about fighting by the end of the play? v How was Sam able to breathe underwater? In real life, what help do humans need to go diving in the sea? v Apart from Sam and the Fisherman, who was the only other creature in the play that needs air to breathe? Kids Story Room – http://kidsstoryroom.com
BLOBFISH Blobfish – Psychrolutes Marcidus The blobfish is a deep sea fish of the family Psychrolutidae. Their habitat is the deep waters off the coasts of mainland Australia and Tasmania. The blobfish live so deep they are rarely seen by humans. Blobfish live at depths between 600–1,200 m where the pressure is several dozen times higher than at sea level. This pressure would likely make gas bladders inefficient for maintaining buoyancy. Instead, the flesh of the blobfish is primarily a gelatinous mass with a density slightly less than water. This allows the fish to float above the sea floor without expending energy on swimming. Its relative lack of muscle is not a disadvantage as it primarily swallows edible matter that floats in front of it. Blobfish eat invertebrates like crabs and sea worms. Blobfish could potentially be caught by bottom trawling with nets as bycatch. Such trawling in the waters off Australia could threaten the blobfish in what may be its only habitat. Kids Story Room – http://kidsstoryroom.com
TUNA Southern Bluefin Tuna - Thunnus maccoyii The Southern Bluefin Tuna is one of the sea's most impressive creatures. A beautiful and powerful fish, it is well suited to a long life endlessly swimming the open seas. An adult Bluefin grows to around 200kg and over 200cm long. Its close relative, the Northern Bluefin Tuna, Thunnus thynnus, can grow to a massive 700 kg. Tuna are true athletes of the ocean, one of the fastest ocean swimmers in the world, and often travel in speed bursts of up to 70km/hr during their migrations over thousands of kilometres of ocean. At these high speeds, the side fins retract into special grooves and the eyes form a smooth surface with the rest of the head in one of the most hydrodynamically advanced bodies in the sea. They must keep moving so that water passes over their gills, carrying oxygen to the muscle system. The slowest a tuna can swim safely to maintain the oxygen flow is to move its own length every second, faster than the fastest human swimmer at top speed. Bluefin gets their incredible physical stamina from a healthy diet of fish, squid and krill. In offshore waters, they also eat small crustaceans and much larger fish. A skilled ocean hunter, the tuna uses its highly developed senses, binocular or stereoscopic vision, extremely sensitive hearing and special chemical detectors, to hunt prey in areas where warm and cold waters meet where there is more food. Few young tuna from each female survive the perils of fishing and other hungry tuna, sharks, fish, birds, even killer whales, and return to the breeding grounds of the Indian Ocean to complete the life cycle. Without fishing pressure, this survival rate would normally ensure a stable population overall, but fishing in the last 20 years has taken many fish before they reach breeding age, which, together with direct fishing of the adult population, has led to a continual decline in the parent stock. Other species of tuna, such as skipjack or yellow fin, which are shorter lived and faster growing can recover from fishing pressure more quickly than the Bluefin. The Southern Bluefin Tuna's naturally slow growth, long life span and its single spawning ground leaves the population particularly vulnerable. Southern Bluefin is considered the ultimate delicacy of the tuna family in Japan. For Bluefin sashimi (raw tuna fillets) people are willing to pay extremely high prices, due its size, color, high fat content, texture and taste. The Southern Bluefin tuna is the most overexploited tuna species. The stocks are heavily depleted. Japan, Australia and New Zealand have imposed restrictions on the catching of this tuna species. This situation has triggered actions by several environmental groups such as WWF and GreenPeace. Many initiatives around the world have been taken to ranch wild caught bluefin tuna in captivity, in Croatia, Spain, Morocco, Australia and Japan. This industry will continue to grow, but due to the slow growth of the tuna and the high costs involved, it is difficult to fulfill the demand for Bluefin. Sustainable Seafood guide: Say No Notes: Predominantly purse seine caught with minor longline catches; overfished with a severely depleted population; assessed as ‘critically endangered’ by the IUCN and threatened in NSW and VIC; Australian fishery mostly targets juveniles for fattening up in sea cage aquaculture operations; long-lived, late- maturing species that is vulnerable to fishing pressure; potential negative ecosystem effects of severe depletion of this high level predator species. Kids Story Room – http://kidsstoryroom.com
PRAWN Western King Prawn – Melicertus Latisulcatus Prawns are invertebrates that live in the sediment, emerging from it for such activities as feeding, moulting and reproducing. These swimming crustaceans have a head, tail, five pairs of swimming legs (pleopods), five pairs of walking legs (pereopods) and numerous pairs of head appendages. The front three pairs of pereopods have claws. Prawns have an external skeleton or shell, which must be shed periodically to enable them to grow. The front part of this shell is called the carapace. It covers the head and protects the vital organs such as the heart, brain, gills and stomach. The prawn can use the muscular tail or abdomen as an escape mechanism in sudden backwards-directed flicks, but the usual method of propulsion is via the swimming legs. Because prawns spend quite a large percentage of their time buried in the bottom sediments, some of the head appendages can be joined together to form a funnel. Water, containing oxygen, can then be drawn down this funnel and over the gills so the prawn can continue to breathe while buried in the sand. Prawns, like most other crustaceans, are able to change colour, depending upon growth, background colouration and time of day. This colouration is due to the colour of the pigment in minute, special cells called chromatophores found in the prawn’s skin beneath the external shell. Their ability to change colour to suit different backgrounds helps the prawns to conceal themselves from predators. Sustainable Seafood Guide: Depends on the region in which captured. Species considered: King, Tiger, Banana, Redspot, School, Endeavour, Black Tiger, Bay & Royal Red Prawn Notes: Trawl caught; concern over damage to seafloor habitats from trawling; bycatch generally higher by weight than retained catch; significant catch of wildlife in some prawn trawls, including sea snakes and seahorses; considerable work still required to reduce bycatch although catch of turtles in tropical prawn fisheries has been significantly decreased Kids Story Room – http://kidsstoryroom.com
LEAFY SEA DRAGON Leagy Sea Dragon – Phycodurus Eques The leafy sea dragon (phycodurus eques) is one of two species of sea dragon found in Australia's southern waters and nowhere else in the world, the other being the weedy sea dragon. Despite its fearsome name, it is incredibly beautiful in shape and colouring and its camouflaging appendages give it a fragile appearance. It is a relative of the seahorse and belongs to the pipefish family. Leafy sea dragons get their common name from the leaf-like appendages on their bodies. They resemble floating pieces of seaweed, which makes them difficult for predators to find in their natural habitat (it also makes them difficult for divers to see too, so anyone who sees one swimming in the wild is exceptionally lucky!). They can reach a total length of 45 centimetres. The leafy sea dragon lives among rocky reefs, seaweed beds, seagrass meadows and on sand patches near weed covered reefs where it looks like drifting seaweed. The leafy sea dragon sucks up its prey using its long pipe-like snout and small mouth. Its favourite food is shrimps or sea lice. These shrimps feed on red algae (seaweeds) that thrive in the shade of the kelp forests where the sea dragons live. Because leafy sea dragons are such fascinating and unique creatures, some people illegally collect them for their aquariums (they are totally protected). Unfortunately, leafy sea dragons that are removed by divers usually die quickly because their captors do not provide them with the correct live food daily. Other major threats to leafy sea dragons include pollution and excessive fertiliser run-off, as well as loss of their seagrass habitat. Being slow moving, they rely heavily on camouflage for survival, but are also equipped with several long sharp spines along the side of the body which are thought to be used to defend themselves against attacking fish. They are also able to change colour to match their surroundings. Sea dragons have eyes that can move independently of one another (while one eye looks one way the other one can look in a completely different direction). Conservation status: Near Threatened Kids Story Room – http://kidsstoryroom.com
SWORDFISH Swordfish – Xiphius Gladius The swordfish is a magnificent solitary predator, extremely fast swimming with a fearsome-looking, pointed sword-like bill for stunning its prey. It can gather speed up to 50mph and relies on speed and agility to catch food. Rare or endangered in many parts of its range swordfish has low resilience to fishing, but is subject to high fishing pressure nonetheless. A number of stocks are overfished and/or include large catches of immature swordfish and by-catch of non-target species including endangered marine turtles. Swordfish are also a predator at the top of the food chain and play an important role in the marine ecosystem. Longline- caught from the Eastern Pacific and Indian Ocean (excluding the Southwest) probably represent the most sustainable fisheries at present. The Swordfish has a very long flattened bill and a strong keel on the caudal peduncle. It has a short-based dorsal fin that is well separated from the second dorsal fin. The species lacks teeth, scales and pelvic fins. It is blue to brown above fading to silver or light brown below. The membrane of the first dorsal fin is usually black. Swordfish are found in marine waters worldwide, with the exception of the cold waters of high latitudes. In Australia the species is known from all marine waters. It is mostly found in deeper water, down to a maximum depth of 650 m, but will sometimes come inshore. Sustainable Seafood Guide: Say No Notes: Longline caught; worldwide declines in Swordfish populations; subject to overfishing in Indian Ocean; important predator species with likely negative ecosystem effects if removed in large numbers; associated bycatch of threatened shark and turtle species in longline fisheries. Kids Story Room – http://kidsstoryroom.com
ABOUT KIDS STORY ROOM – kidsstoryroom.com Kids Story Room is a children’s story podcast created by actor Anna Steen. All our stories are original and lovingly crafted for young people. We have been creating stories since November 2018 and have a wonderful global audience. We are delighted to be able to create an audio drama for National Science Week 2020. CALL OF THE BLOBFISH by Anna Steen Cast Narrator/Tuna/Sam Anna Steen Blobfish/Swordfish/Tom Christopher Pitman Prawn/Dolphin Lizzy Falkland Leafy-Sea Dragon Heather Steen Interview – thanks to Georgie Kenning from the Marine Discovery Centre, Adelaide. Technical Production: Anna Steen This project is made possible thanks to a South Australian Community National Science Week grant. Kids Story Room – http://kidsstoryroom.com
COLOURING IN Kids Story Room – http://kidsstoryroom.com
FIND-A-WORD Kids Story Room – http://kidsstoryroom.com
MARINE EDUCATION RESOURCES Marine Discovery Centre marinediscoverycentre.com.au The Marine Discovery Centre in South Australia is a wonderful place – providing inspirational learning experiences whilst encouraging community engagement and activity in protecting marine environments. They also have a fabulous online shop with excellent and fun resource material. Sustainable Seafood Guide goodfish.org.au Australia’s Sustainable Seafood Guide provides a comprehensive insight into the impact of our seafood choices. There is a wealth of information on this site and it provides an easy traffic light system to highlight how sustainable our preferred seafood is. The criteria is based upon the latest research undertaken by fisheries experts and encompasses both wild caught and farmed seafood. Australian Marine Conservation Society marineconservation.org.au The Marine Conservation Society are doing incredible work in protecting the health of the ocean. You can sign up, join campaigns, get informed with the latest research and become a part of a national community committed to doing the best for our oceans and the planet. Ocean Collectiv Solutions for a healthy ocean. This website is fantastic, full of amazing information. Ayana Johnson who is the founder and CEO is inspirational. To listen to an incredible podcast look up Ayana Johnson on the Ologies podcast by Alie Ward. It’s so good – but tailored to adults rather than small fry. oceancollectiv.co Kids Story Room – http://kidsstoryroom.com
More Marine Education Online Marine Education Society of Australasia Loads of free teacher resources mesa.edu.au Marine Teachers Association of Queensland marineteachers.org.au Oceanic Biodiversity Information Service (OBIS) Education Image library, lesson plans and much more. Home: obis.org The World Ocean Classroom worldoceanobservatory.org/content/ocean-today Reef Watch A community reef monitoring project reefwatchsa.org.au Bureau of Meteorology This page has lots of lesson plans and student worksheets on many different topics associated with weather and climate. bom.gov.au/lam/Students_Teachers/learnact.htm#sose Department of Environment & Heritage (SA) Coast & Marine Branch environment.sa.gov.au/topics/coasts Marine Life Society of SA (MLSSA) mlssa.org.au SARDI Aquatic Sciences pir.sa.gov.au/research Conservation Council of South Australia conservationsa.org.au Fisheries Research and Development Corporation frdc.com.au Environment Protection Authority epa.sa.gov.au OceanWatch Australia/ Seanet http://www.oceanwatch.org.au/ CSIRO Marine https://research.csiro.au/oa-idc/ Australian Institute of Marine Science http://www.aims.gov.au/ Carpentaria Ghost Nets http://www.ghostnets.com.au/index2.html The Physical Ocean http://www.worldoceanobservatory.org/index.php?q=physicalOcean.html Kids Story Room – http://kidsstoryroom.com
Census of Marine Life https://oceanleadership.org/ Deep Sea Conservation Coalition http://www.savethehighseas.org/ The Ocean Project http://www.theoceanproject.org/ Woods Hole Oceanographic Institute http://www.whoi.edu/k-12/k12-resources.html NOAA National Oceanographic Data Centre http://www.nodc.noaa.gov/ Ocean Planet Resource Room http://seawifs.gsfc.nasa.gov/OCEAN_PLANET/HTML/ocean_planet_resource_room.html Gulf of Maine Research Institute https://www.gmri.org Kids Story Room – http://kidsstoryroom.com
Make a pull-through that shows the different zones of life in the ocean Traveling through the ocean depths in small submersibles, ocean explorers have Objectives: been eye to eye with glowing hatchet fish, sharp-nosed swordfish, creeping sea Describe the three zones cucumbers, and other ocean inhabitants. In the first part of this activity, your of life in the open ocean. kids can make a pull-through that shows some of these creatures. And in the Give an example of an second part, they can use poetry to describe these animals and the different animal that lives in each zones where they live. zone and explain how it Before you begin the activity, make a copy of the pull-through cover. is adapted to its habitat. Cut along the dashed line below the pull-through cover. Then place the cover in the center of an 8 1/2 x 11" piece of paper and make enough copies of it for your Ages: Grades 3-8 group. Materials: PART 1: DIVING THROUGH THE ZONES construction paper glue Begin by asking the kids to think about how the ocean’s surface waters differ scissors from the waters that are thousands of feet deeper. Using the background crayons or markers information at the end of lesson, talk about the kids’ ideas and explain the stapler differences between the sunlight, twilight, and midnight zones. (You may want tape to copy the diagram below onto a chalkboard or piece of easel paper.) paper Next tell the kids that scientists are most familiar with the animals and pencils plants that live in the sunlight zone, since these waters are close to the surface chalkboard or easel and relatively easy to study. paper (optional) But people know a lot less about life in the deeper parts of Subjects: Science and Language the ocean. Since the 1960s, Arts scientists have traveled to these depths in submarine-like vehicles called submersibles. (You may want to show the kids a picture of a submersible such as Alvin.) Although they aren’t very big (Alvin is 24 feet long and holds only three people), submersibles can withstand the intense pressure of the deep sea. Next tell the kids that they’ll be making a pull-through that will give them an idea of what a scientist might see on a submersible dive to the bottom of the Atlantic Ocean. Pass out copies of the pull-through cover (at the top of the following page) that you made earlier, construction paper, scissors, markers or crayons, and glue, and have the kids follow the directions below to make a pull-through. National Wildlife Week March 19-35, 2012 www.nwf.org/nationalwildlifeweek Kids Story Room – http://kidsstoryroom.com
Pull-through Cover MAKING THE PULL-THROUGH The Inside Strip 1. Color the three different zones on the pull-through strips. (The twilight zone is cut in half.) Color the sunlight zone (to 300 feet) light blue, the twilight zone (to 3000 feet) dark blue, and the midnight zone (to bottom) black. Don’t color the creatures! 2. Glue the pull-through strips onto a piece of construction paper. (Use a thin layer of glue and spread it evenly over the entire back of the paper.) 3. Cut along the dashed vertical lines so that you have two long strips. Cut off all of the excess construction paper, except for the paper at the top of the twilight zone. (Leaving extra construction paper at the top of the twilight zone will make the strip sturdier.) 4. Put the strips together so that the twilight zone is complete. Tape along both sides of the strip (see diagram on next page). THE COVER 1. Cut out the circle on the pull-through cover. (It may be easier to first poke a hole in the center of the circle with a sharp pencil.) Also cut out the small box next to the circle. 2. Glue the cover to a piece of construction paper. Be sure to put a thin line of glue only along the vertical sides of the cover, leaving the bottom and top unglued (see diagram on next page). When the two parts are completed, have the kids insert the pull-through into the cover so that the top of the sunlight zone shows through the viewing port. (The depth and temperature window should be to the right of the viewing port.) Then, to help keep the pull-through “on line” as it moves through the cover, have the kids staple the cover together as shown in the diagram above. National Wildlife Week March 19-35, 2012 www.nwf.org/nationalwildlifeweek Kids Story Room – http://kidsstoryroom.com
Assembling the Pull-through Let the kids “descend” to the bottom a few times on their own. Point out that because some animals would be close to the submersible and others would be farther away, some appear larger than others. (Refer to information under “Who’s Who in the Zones” below for actual sizes.) Also be sure to point out that the depth scale isn’t in proportion for all three zones. To show the diversity of life throughout the ocean, we gave all the zones equal room on the pull-through. But the twilight and midnight zones are larger than the sunlight zone. You might also want to point out that the temperatures on the pull-through are average temperatures. In the ocean, water temperatures may vary depending on the season and location. Next pass out copies of “Who’s Who In the Zones”. If you’re working with younger kids, go over the information on the page as a group. Older kids can read the page on their own to learn about each of the animals. (They can identify the animals by matching the numbers next to the animals’ names with the figures in the margin.) Have the kids color in all the animals on the pull-through according to the information on their sheets. Afterward ask the kids if they can make any generalizations about the characteristics of life in the different zones. (Animals in the twilight and midnight zones are generally smaller than those in the sunlight zone, and many animals in the twilight zone are luminescent. Many animals in the sunlight zone have dark backs and light bellies. When viewed from above this countershading helps them blend in with the darker waters below, and when viewed from below, it helps them blend in with the lighter waters above. See the background information below for other generalizations.) Also explain that although all these animals live in the Atlantic Ocean, it’s unlikely that you’d find all of them in the same place at the same time. It’s also unlikely that you’d see so many animals in the same small area, since life is widespread in the open ocean—especially in the twilight and midnight zones. To finish up this part of the activity, the kids can decorate the pull-through cover to resemble what they think the inside of a submersible might look like. National Wildlife Week March 19-35, 2012 www.nwf.org/nationalwildlifeweek Kids Story Room – http://kidsstoryroom.com
National Wildlife Week March 19-35, 2012 www.nwf.org/nationalwildlifeweek Kids Story Room – http://kidsstoryroom.com
PART 2: PICTURE POETRY As a group, make a list of adjectives that describe the three zones of life and the creatures that live in them. Words such as sunny, sparkling, black, dim, shadowy, murky, and crushing could describe the zones. And fast, speedy, strong, sharp-toothed, ugly, scary, floating, light-bearing, and big-mouthed could describe some of the animals shown in the pull-through. Tell the kids that these words help to create images of the different zones and the creatures that live in them. But these words can be even more descriptive if they’re arranged to form a picture. Copy the example below on the board or easel paper. Tell the kids that this form of poetry is called picture poetry. They'll be making up their own picture poems to describe the creatures and/or zones they learned about from the zone pull-through. Explain that they can use words from the list on the board, along with any other words they think of. Also explain that their poems don't have to rhyme and that they can use as few or as many words as they want to create a picture. Pass out paper and pencils to the kids and give them time to make up some picture poems. Afterward, have volunteers share their poems with the rest of the group. BACKGROUND: LIFE IN THE OCEAN The Ocean, From Top to Bottom Seaweeds, sea snakes, whales, whelks, penguins, porpoises, tuna, and tunicates are just a few of the many organisms that live in the ocean. Most marine plants and animals are adapted to living in one of three regions-the sunlight, twilight, or midnight zone. These zones are defined by the presence (or absence) of light. And they differ from one another in temperature, amount of pressure, and nutrient supply. (Instead of sunlight, twilight, and midnight zone, some marine scientists use the terms surface waters, mid-waters, and deep sea to describe the different regions in the ocean. And other scientists prefer to divide the ocean into two parts—a light and dark region.) Here’s a look at each light zone and some of the plants and animals that live in them: LIFE AT THE TOP Sunlight on the Surface: Light streams through the “sunlight zone,” the top layer of the ocean. This is the ocean’s greenhouse, the only zone where there’s enough light to support National Wildlife Week March 19-35, 2012 www.nwf.org/nationalwildlifeweek Kids Story Room – http://kidsstoryroom.com
plant life. On the average, the sunlight zone ends at about 300 feet. But this lower boundary varies from just a few feet to more than 600 feet, depending on the part of the world and even the time of year. Although the sunlight zone makes up only a small part of the ocean, more than 90 percent of all known marine species live here. Drifters and Swimmers: Many animals in the sunlight zone get around either by drifting or swimming. The drifters include jellyfish, young crabs and fish, and microscopic plants and animals. These organisms, collectively called plankton, move along with the winds and currents. Some plankton have a limited swimming ability and can migrate daily in a vertical direction. Dolphins, swordfish, sea turtles, and other swimmers make their own way through the ocean. Many have muscular, streamlined bodies that help them move through the water. Precious Plankton: Planktonic organisms provide the basic source of food in the surface waters. Millions of microscopic phytoplankton (plant plankton) grow near the surface, bathed in sunlight and nourished by nutrients such as oxygen, carbon, nitrogen, and phosphorus from the surrounding water. Slightly larger zooplankton (animal plankton) feed on phytoplankton or on each other. In turn, animals such as fish, jellyfish, and even whales eat zooplankton. And many plankton-eating animals are preyed on by seabirds, seals, sharks, and other meat eaters. A Changing Place: Daily changes in sunlight affect organisms that live in the upper waters. For example, some kinds of fish remain far below the surface during the bright, sunlit hours, then feed closer to the surface at night when darkness helps hide them from predators. Seasonal variations in sunlight also affect some plants and animals. In temperate and polar regions, surface waters warm up in the spring and help stimulate explosive plankton growth. Some animals, such as gray whales, make seasonal migrations to gorge themselves in these plankton-rich areas. Life from Death: When they die, inhabitants of the sunlight zone become food for animals that live deeper in the ocean. Dead plants and animals sink toward the ocean floor, gradually decomposing along the way and releasing precious nutrients that had been locked away in their body tissues. Some remains of dead plants and animals fall into deeper waters, where a variety of animals may feed on them. Even wastes from animals in the surface waters provide nutrients for organisms that live in the deep sea. A Continental Close-Up: Life is most abundant in one special part of the sunlight zone-the waters over the continental shelves. In many parts of the world, these shallow waters harbor rich populations of plankton, fish, mammals, and birds. (In fact, more than half of the world’s commercial fish catch comes from these waters.) And the shelf floor itself teems with animals that crawl on, burrow through, swim near, or stick to the bottom. The abundance of nutrients in the sunlit continental waters promotes this amazing productivity. In some parts of the world, nutrients are brought to the shelf waters by upwellings, waters that move up the continental slope from deep in the ocean. Nutrients from the decomposing remains of dead plants and animals are also scooped off the shelf floor itself and carried closer to the surface by water that the wind has stirred up. INTO THE MURKY MID-WATERS Deeper and Dimmer: With increasing depth, the water pressure increases, the temperature drops sharply, and the light gradually dims. The next layer of the ocean, the “twilight zone,” extends from the lower boundary of the sunlight zone down to about 3000 feet. Most of the sunlight has National Wildlife Week March 19-35, 2012 www.nwf.org/nationalwildlifeweek Kids Story Room – http://kidsstoryroom.com
been absorbed by the upper layers of water, leaving the twilight zone cast in dim, blue light that barely forms silhouettes. For Animals Only: Plants can’t grow in these dimly lit mid-waters. Limited by a “plantless” food supply, the animals in this zone are smaller and less abundant than animals that live closer to the surface. Some twilight-zone dwellers, such as lantern fish and mid-water zooplankton, swim up into the sunlight zone each night to feed on the more plentiful food there. Others, such as hatchet fish, prey on animals within the twilight zone. And many twilight-zone animals survive by eating large pieces of animal and plant remains that drift down from the sunlight zone. Lights On: Bioluminescence, the production of light by living creatures, is another common characteristic of organisms in the twilight waters. Many mid-water shrimp, squid, fish, and other animals have special light-producing organs on their bodies. Scientists think these lights may attract prey, identify potential mates, or surprise predators. THE DARK DEEP SEA Life in the Pits: Beginning at about 3000 feet and stretching to the ocean floor, the “midnight zone” makes up about three-quarters of the total ocean. That’s an estimated 250 million cubic miles of water! Life isn't easy in the ocean’s “basement.” The water pressure here may exceed two tons per square inch, the temperature hovers near freezing, and it's completely dark. And these harsh conditions remain the same throughout the day and year. Scientists estimate that only one percent of all ocean species live in this zone. Stunted and Slow: If you looked at a close-up photo of a fangtooth, angler fish, or other deep-sea predator, you’d probably be startled by its gaping mouth and sharp teeth. But, like many deep-sea animals, these fierce-looking predators are only a few inches long. In addition to being small, most deep-sea animals have a very low metabolic rate, which means that their digestive rate, heart rate, and other body functions are very slow compared to those of most other marine animals. Because of this, midnight-zone animals tend to grow very slowly and live for a long time. Super Scavengers: Animal remains from the ocean’s upper layers are a major source of food in the midnight zone. Chunks of flesh from the carcasses of whales and other large animals are quickly seized by active scavengers such as rattail fish, hagfish, sleeper sharks, and an occasional deep-sea octopus. Crabs, snails, shrimp, and smaller scavengers feed on the scraps left by larger animals. On the Floor: The flat, largely featureless abyssal plains stretch across much of the deep-sea floor. Deep layers of silt called “ooze,” formed over thousands of years by a steady rain of plankton remains, cover the plains. For the most part, the deep-sea floor is a pretty deserted place. That's because there’s not a lot of food that far down. Some floor-dwelling animals, such as sea pens, are anchored in the ooze and filter tiny food particles from the surrounding water. Others, such as sea cucumbers and acorn worms, crawl along or burrow into the floor in their search for nutrients. Hot Spots: Special vent communities found along deep-sea ridges are the exception to almost every generalization about the midnight zone. For one thing, a great number of animals live in a small area in these communities. They grow quickly and can become relatively large. And, unlike most other inhabitants of the deep-sea floor, these creatures don't depend on plant and animal remains from the surface waters (and ultimately, sunlight) for food. National Wildlife Week March 19-35, 2012 www.nwf.org/nationalwildlifeweek Kids Story Room – http://kidsstoryroom.com
These special deep-sea communities are clustered around hydrothermal vents—cracks in the Earth’s crust that spew out hot, mineral-rich water. Special chemosynthetic bacteria use hydrogen sulfide that pours from the vents for energy to make food-in much the same way that green plants use sunlight in photosynthesis. All of the other animals living around the vents depend on these bacteria for food. Anemones, for example, filter the bacteria from the water. Others, such as eight-foot-long tube worms and foot-wide clams, have formed a special partnership with the bacteria. In place of a “gut,” the worms and clams have masses of bacteria inside their body tissues that provide them with nutrients. WHO’S WHO IN THE ZONES Sunlight Zone 1. Portuguese man-of-war purple body with long, purple and white tentacles tentacles may be over 100 feet long small fish are paralyzed by stinging tentacles, then eaten 2. Flying fish Doesn’t really fly—gains speed as it swims, then leaps from water and glides body is silver about 9 inches long 3. Ocean sunfish about 15 feet long and weighs more than a ton body is gray or brown eats jellyfish 4. Striped dolphin eats small fish and squid about 8 feet long back is dark blue and belly is white 5. Sperm whale about 56 feet long and weighs about 43 tons body is gray or black may eat a ton of food a day commonly dives to depths of more than 3000 feet in search of giant squid and other prey 6. Blue marlin about 12 feet long and weighs about 1000 pounds swipes its swordlike nose through schools of fish, then eats wounded ones back is blue and belly is white 7. Bluefin tuna usually swims in schools about 14 feet long and weighs about 1800 pounds back is blue-black, sides are silver-gray, and belly is white National Wildlife Week March 19-35, 2012 www.nwf.org/nationalwildlifeweek Kids Story Room – http://kidsstoryroom.com
8. Thresher shark about 16 feet long and weighs about 500 pounds back is olive-green or brown-gray and belly is white swims into schools of fish; stuns some fish by hitting them with its long tail, then eats them Twilight Zone 9. Lantern fish 2 to 3 inches long swims closer to surface at night to feed on zooplankton body is pale brown or gray and speckled with many lights 10. Viperfish jaws can open wide to catch large prey about 8 to 10 inches long body is dark brown or black single line of lights along sides of body lighted lure helps attract prey 11. Hatchet fish feeds on zooplankton and shrimp 3 to 4 inches long sides of body are silvery, with lights along belly 12. Mid-water jellyfish about 3 inches wide eats small fish and zooplankton body is maroon and white 13. Rattail fish about 2 1/2 feet long body is gray feeds on lantern fish, shrimp, and the remains of dead animals Midnight Zone 14. Opossum shrimp 4 to 6 inches long body is red not a true shrimp 15. Snipe eel long jaws catch shrimp and zooplankton about 1 1/2 to 3 1/2 feet long body is brown or black 16. Black swallower about 6 inches long body is black can swallow fish that are 8 to 10 inches long stomach stretches to hold large prey 17. Vampire squid 5 to 8 inches long body is black with shades of purple National Wildlife Week March 19-35, 2012 www.nwf.org/nationalwildlifeweek Kids Story Room – http://kidsstoryroom.com
body speckled with small lights not a true squid, but a close relative 18. Angler fish about 3 to 6 inches long body is dark brown or black eats fish, squid, zooplankton, and worms females have a light at the end of a stalk that helps them attract prey and mates 19. Tripod fish about 12 inches long body is dark brown long, stiff fins help it stand on soft bottom 20. Sea cucumber about a foot long crawls over bottom, feeding on small bits of food body is usually dark violet Adapted from “From the Surface to the Sea Floor”, Ranger Rick’s NatureScope Diving Into Oceans. National Wildlife Federation, 1998. National Wildlife Week March 19-35, 2012 www.nwf.org/nationalwildlifeweek Kids Story Room – http://kidsstoryroom.com
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