Hudson Canyon Expedition Fishy Deep- Designs!

Focus Materials Adaptations of living in the mesopelagic and  Bucket (with handle) of water bathypelagic zones of the deep  Ice  Thermometer Grade Level  Representative images of mesopelagic and bathy- 7 - 9 pelagic fishes (can be accessed from multiple sources listed in Resources section) Focus Questions  One blank and two completed “General How do the characteristics of at 200 Characteristics of in Major Ocean Zones” meters differ from those at 1000 meters? charts for every team of 2-4 students  1 ziplock sandwich bag for every team of 2-4 How might fishes living between 200 meters and students 1000 meters of water differ from those living at  Optional: “Marine : Secret depths greater than 1000 meters? Lights in the Sea” 26-minute video. Available by sending an e-mail to Ocean Research and Learning Objectives Conservation Association at inquiries@oceanrecon. Students will be able to identify the basic charac- org or by direct order on their Web site at www. teristics of the mesopelagic and bathypelagic zones oceanrecon.org with regard to depth, temperature, pressure, light  Optional: “The Bioluminescence Coloring Book,” level and food availability. by Edith Widder, Ph.D., available from the Ocean Research and Conservation Association Students will be able to explain several adaptive using the contact information above. characteristics of fish living in mesopelagic and  Optional: “Night Life: Creatures of the Deep” bathypelagic zones. 28-minute video created by the New England Aquarium and Bermuda Underwater Exploration Students will learn that many fishes are biolumines- Institute. To order, send an e-mail message to cent. the New England Aquarium at [email protected]

Students will be able to explain some of the adap- Audio/Visual Materials tive functions of bioluminescence.  Internet-connected computers, if possible, for stu- dent research Students will conduct independent research about  Internet-connected computer with LCD projector, if the habitat requirements of a chosen of possible, for showing images of fish deepwater fish.

 Hudson Canyon Expedition (Grades 7–9) Adaptations of fishes in mesopelagic and bathypelagic zones of the deep ocean oceanexplorer.noaa.gov

Teaching Time enough to support plant growth, the availability of 2 45-minute class periods (more if videos are food, as compared to the epipelagic zone, is much included) reduced. Only about 20% of the food produced in the epipelagic zone makes its way to underlying One week for student independent research waters of the .

Seating Arrangement It is in the mesopelagic zone that a transition 2-4 students per group between the warm surface waters of the epipelagic and the constant cold temperatures of the bathy- Maximum Number of Students pelagic zones (see below) occurs. This transition in 36 temperature is called a . At 200 meters, the temperature averages roughly 23 degrees Key Words Celsius and then declines linearly with depth to Photic about 4°C at 1000 meters. that migrate Aphotic through the mesopelagic zone experience quite a Epipelagic zone bit of change in temperature, while animals that Mesopelagic zone tend to stay at the same depths experience far Bathypelagic zone fewer fluctuations. Twilight zone Midnight zone Since pressure increases with depth (one atmo- Bioluminescence sphere per 10 meters or 14.6 pounds per square Counterillumination inch per 10 meters), organisms living in the meso- are under a quite a bit of pressure! Background Information The pressure at 200 meters is equivalent to 21 The ocean is divided into three zones based on atmospheres or 307 pounds per square inch and depth. The upper 200 meters of the ocean is at 1000 meters is equivalent to 101 atmospheres termed the . This zone is penetrated by or 1475 pound per square inch. sunlight and plants thrive. Food is relatively abun- dant. This region is also called the epipelagic zone Fishes of the Mesopelagic Zone and this term refers to the upper layer of the open Many midwater fishes have light organs, or ocean or “top pelagic” zone in the ocean. , that produce light. The biologi- cal production of light is called bioluminescence. The Mesopelagic Zone Bioluminescence has evolved in many different Immediately below the epipelagic zone lies the species and this suggests its importance to survival mesopelagic zone and this zone extends from 200 in the . There are several reasons why meters to 1000 meters in depth. This zone is also an organism may produce light. Some of these called the middle pelagic zone. In the mesopelagic strategies are listed below, with an example of an zone, dim light still exists but not at high enough organism that uses that strategy. levels to support plant growth. This zone has yet another name and has been coined the “twilight” Counterillumination or “To Hide”: Many animals that zone which refers to the dissipation of light with move up and down in the twilight zone have light increasing depth. At the lower depths of the twi- producing organs on their ventral surfaces. They light zone, light penetration becomes minimal and are able to increase the light level of their ven- darkness abounds. Since the sunlight available to trally-located lights as they move into shallower, the depths of the mesopelagic zone is not sufficient light-richer waters and dim them as they descend  Hudson Canyon Expedition (Grades 7–9) oceanexplorer.noaa.gov Adaptations of fishes in mesopelagic and bathypelagic zones of the deep ocean

into deeper waters. In this manner, they become exhibits a bioluminescent “burglar alarm” display somewhat invisible to predators swimming above meant to attract attention just as a burglar alarm or below them. A fish using counterillumination does. If the is caught in the clutches of a would have a ventral surface that blends in with the predator, its only chance of escape is to “call” lighter waters above when viewed from a predator for help with its eye-catching light display; i.e. to from below. This is very similar to attract the attention of a bigger predator that may (animals with lighter ventral surfaces and darker attack the jellyfish’s attacker, thereby affording the backs, or dorsal surfaces) but uses light to achieve jelly the chance of escape. (See http://www.oceanex- the same effect. Shining tubeshoulders and bristle- plorer.noaa.gov/explorations/05deepscope/background/eyeinsea/ mouths both have ventrally-located lights! eyeinsea.html)

The use of photophores for counterillumination is Most mesopelagic fishes are quite small; food is a feature, in particular, which characterizes meso- scare and the limited resources available do not pelagic fishes. Therefore, if you observe a fish with support large body sizes. Bristlemouths and lan- photophores on its ventral surface, the fish is very ternfish are the most abundant in this zone. Since likely to be a fish which migrates vertically and food is scare, many midwater fishes have large uses counterillumination as a survival strategy. mouths relative to their body size, unhingeable jaws that can be opened wide to swallow prey, Attracting a Mate: Many organisms have species- and large teeth. If a rare meal swims by, a hungry specific light patterns and in some, specific to a midwater fish does not want to miss an opportunity certain sex. In a dark environment, this is a great to dine! way to get a date! and lantern fish both are thought to produce light to attract a mate. (For In the twilight zone, there are numerous fishes that an anglerfish image, see http://oceanexplorer.noaa.gov/ are black or red. At depth, these fishes are not vis- explorations/04deepscope/background/deeplight/media/fig3c. ible. The black animals absorb all colors of light html) available and the red animals appear black as well; there is no red light to reflect and their bod- Attracting Prey: Some organisms have lighted body ies absorb all other available wavelengths of light parts that they use to attract prey. Gulper eels have (see the 5th and 6th grade activity entitled “What’s a light at the end of their tail. It is thought that this Bright Red and Invisible?” for more in-depth infor- might use the light to attract prey to its huge mation). Thus red and black animals predominate. mouth. Since the color blue penetrates best in water, there simply are not that many blue animals in the Escape Tactic: Some organisms will use light to tem- midwater regions of the ocean; their entire bod- porarily distract or divert predators. Some animals ies would reflect the blue light and they would be will shoot out “clouds” of light. The goal is for the highly visible to predators. (See “All That Glitters” light to confuse or distract a predator, while the lesson plan, p. 100 “un-lighted” animal attempts to escape. The deep http://oceanexplorer.noaa.gov/edu/curriculum/section5.pdf) sea shrimp, Acanthephyra purpurea, is an example of animal which spews bioluminescence to blind Fishes in the midwater zone can typically be or distract a predator. (For an image of this, see grouped into two distinct categories; those that http://oceanexplorer.noaa.gov/explorations/04deepscope/back- swim up to the epipelagic zone at night (verti- ground/deeplight/media/fig3c.html) cal migrators) and those that remain at particular depths within the mesopelagic zone. Midwater The common deep-sea jellyfish Atolla wyvillei fishes that make vertical migrations are typically

 Hudson Canyon Expedition (Grades 7–9) Adaptations of fishes in mesopelagic and bathypelagic zones of the deep ocean oceanexplorer.noaa.gov

black or silver, have large eyes to capture available fishes are often absent or reduced. Since food light, a large mouth, photophores and small body is so scarce, energy conservation is the name of size. They also tend to have well-developed swim the game! Most of the fishes are sluggish or tend bladders, muscles and bones; all structures that to stay in one place. They have watery, flabby aid in migration. Fishes that do not migrate tend to muscles, weak skeletons, no scales and poorly be black, red or silver, have large eyes, and have developed systems (nervous, respiratory and diges- large mouths, photophores and small body size. tive). Almost all of the bathypelagic fishes lack a They tend to lack a , however, and swimbladder. Most bathypelagic fishes have huge they have weak bones and flabby muscles. mouths, are small and have black bodies.

Bathypelagic Zone Learning Procedure Below depths of 1000 meters lies a world of per- Step One: petual darkness. The depths below 1000 meters 1. Using a diagram, show students how the ocean comprise the bathypelagic or “deep pelagic” zone. has been divided into three zones (epipelagic, Due to its constant darkness, this zone is also called mesopelagic, and bathypelagic) based on depth. the midnight zone. Only about 5% of the food pro- duced in the epipelagic zone makes it way down to 2. Ask students what they think the temperature, the bathypelagic zone. Food is a scarce commodity pressure, light level and food availability in the in the midnight zone. mesopelagic and bathypelagic zones might be.

The temperature in the bathypelagic zone, unlike 3. Describe the temperature, pressure, light level that of the mesopelagic zone, is constant. The tem- and food availability in the mesopelagic and perature in this zone never fluctuates far from a bathypelagic zones. chilling 4°C. 4. Use a bucket of water to demonstrate pressure. The pressure in the bathypelagic zone is extreme Ask a student to lie down on his/her back at and at depths of 4,000 meters, reaches over 5850 the front of the classroom. Ask the student to pounds per square inch! Though quite a harsh breathe in and out. Now gently place a bucket of environment, the bathypelagic zone comprises the water on the student’s lung area. Hold onto the single largest habitat on Earth. handle of the bucket to provide support. Ask the student to breathe and to tell the class if it was Fishes of the Bathypelagic Zone more or less difficult to inhale with a bucket of In the bathypelagic zone, bioluminescence is as water sitting on top of their chest. Ask the entire prevalent as in the mesopelagic zone. However, in class how it might feel to breathe with 50, 100 the complete darkness of the bathypelagic zone, and 1000 buckets of water sitting on top of their there is no need for countershading and biolumi- lungs. nescence is not used for this purpose. Bathypelagic fishes tend to have fewer photophores than meso- 5. Remove about half of the water and fill the buck- pelagic fishes and the photophores tend to be on et with ice. the head and sides of the fishes in bathypelagic fishes whereas mesopelagic fishes often have pho- 6. Use the bucket of ice water to convey tempera- tophores on their ventral surfaces. ture. Have a student come to the front of the class and submerge his/her hand in the ice water. Ask Fishes of the midnight zone usually have no need how it feels and whether they would like to take for large, sensitive eyes and the eyes of these a bath in water just as cold.

 Hudson Canyon Expedition (Grades 7–9) oceanexplorer.noaa.gov Adaptations of fishes in mesopelagic and bathypelagic zones of the deep ocean

7. Take a temperature reading of the ice water Step Three: using a thermometer and convey reading to the 14. Provide students with the list of fishes from the class. Relate temperature reading to the tem- mesopelagic and bathypelagic zone below. perature in mesopelagic and bathypelagic zones. Allow them to select one fish and research the habitat requirements of the fish. Students should 8. Ask students to describe the fishes they think would include the following in their report: a picture live in the mesopelagic and bathypelagic zones. of the fish, the size of the fish, the depth(s) where the fish can be found, the general habitat 9. Brainstorm the characteristics of mesopelagic and requirements of the fish and special adaptations bathypelagic fishes and record the characteristics for survival. Also require that students include on the board. the and species of the fish they research and describe; many of the fishes listed below Step Two: include several different species that will differ in 10. Prepare the “playing boards” for this portion of habitat (i.e., some are found in the the activity: mesopelagic zone while others are found in the a. Copy one blank “General Characteristics of bathypelagic zone). Fish in Major Ocean Zones” chart for every Anglerfish team of students. If you laminate these charts, Bristlemouth you can use them repeatedly. b. Copy two completed “General Characteristics Hatchetfish of Fish in Major Ocean Zones – Answer Key” Gulper eel charts for every team of students. Laminate one of each set of these completed charts. c. From the unlaminated completed chart, cut Dragonfish the “answers” apart into individual rectangles. Laminate and cut out each individual rectangle Longnose lancefish for repeated use. Place each set of rectangles Sabertooth fish in one ziplock sandwich bag for use by one student team. These are the “playing pieces.” Note: Descriptions of some of these animals can be found on the Monterey Bay Aquarium’s Web site 11. Give each team of students one blank “General http://www.mbayaq.org/efc/living_species/. Although this Characteristics of Fish in Major Ocean Zones” site provides distribution of animals in the Pacific, chart and one set of playing pieces. Tell the stu- students can access great photographs and some dents to fill in the blanks with the playing piece good, basic information. answers. When they have completed their chart, give them a laminated completed chart with The BRIDGE Connection which to check their answers. Go to the BRIDGE Web site at http://www.vims.edu/ bridge/ 12. Once all teams have finished, discuss the results. Under the Navigation side bar click on Human Were there any answers which surprised the Activities to learn more about the technology used students? Ask students to offer suggestions about to study deep sea environments. the functions of the various adaptations. The “ME” Connection 13. Show one or both of the recommended videos If the bathypelagic zone of the ocean represents to students. over 80% of all habitats on Earth, why might it

 Hudson Canyon Expedition (Grades 7–9) Adaptations of fishes in mesopelagic and bathypelagic zones of the deep ocean oceanexplorer.noaa.gov

be important to study this habitat? How might Other Links and Resources discoveries in this deep sea habitat affect your life The Web links below are provided for information- someday? al purposes only. Links outside of Ocean Explorer have been checked at the time of this lesson plan’s Connections to Other Subjects publication, but the linking sites may become out- Art dated or non-operational over time. Using art materials, create a canyon habitat. Place fishes at the proper depths within the habitat. For Resources information and canyon images, visit the Hudson Web sites for student research: Canyon expedition Ocean Explorer Web site at http://www.mbayaq.org/efc/living_species/ http://www.oceanexplorer.noaa.gov/explorations/02hudson/wel- http://www.mbari.org/ come.html Note: This builds on the evaluation tool http://www.biolum.org listed below. http://www.lifesci.ucsb.edu/~biolum/ http://www.bioscience-explained.org/EN1.1/features.html Mathematics http://www.pbs.org/wgbh/nova/abyss/ One atmosphere is equivalent to 14.7 pounds http://oceanlink.island.net/oinfo/deepsea/deepsea.html per square inch. At the surface of the ocean, one http://www.divediscover.whoi.edu atmosphere of pressure exists due to the atmo- http://www.nationalgeographic.com sphere above the water. Pressure in the ocean then http://www.marine.whoi.edu/ increases one atmosphere with every increase in http://www.oceanexplorer.noaa.gov/technology/technology.html 10 meters of depth. How many pounds per square http://www.ocean.udel.edu/deepsea inch of pressure would exist at 200 meters? At http://www.pbs.org/wgbh/nova/abyss/ 1000 meters? http://www.whoi.edu/WHOI/VideoGallery/vent.html

Evaluation National Science Education Standards Using art materials (construction paper, aluminum Content Standard A: Science as Inquiry foil, glow-in-the dark paint, etc.), have students cre- • Abilities necessary to do scientific inquiry ate a three-dimensional model, to scale, of the fish • Understandings about scientific inquiry they researched. Content Standard C: Life Science Extensions • Structure and function in living systems Have students visit the http://oceanexplorer.noaa. • Populations and ecosystems gov Web site to find out more about the Hudson Content Standard D: Earth and Space Science Canyon and Mountains in the Sea expeditions. • Structure of the Earth system

Optional Extension Ocean Literacy Essential Principles and Fundamental Have students paint the organisms featured in the Concepts “Bioluminescence Coloring Book” (listed in the Essential Principle 5. Materials section). Display the completed paintings The ocean supports a great diversity of life and ecosystems. in a dark classroom; observe and discuss. Fundamental Concept a. Ocean life ranges in size from the smallest to the largest animal that Multimedia Learning Objects has lived on Earth, the blue whale. Click on the links to Lesson 6 for interactive mul- Fundamental Concept d. Ocean biology provides timedia presentations and activities on Deep Sea many unique examples of life cycles, adaptations Benthos. and important relationships among organisms  Hudson Canyon Expedition (Grades 7–9) oceanexplorer.noaa.gov Adaptations of fishes in mesopelagic and bathypelagic zones of the deep ocean

(symbiosis, predator-prey dynamics and energy Acknowledgements transfer) that do not occur on land. This lesson plan was produced by Stacia Fletcher, Fundamental Concept e. The ocean is three-dimen- South Carolina Aquarium, Charleston, SC and sional, offering vast living space and diverse habi- modified by Cindy Renkas, NOAA Ocean tats from the surface through the to Exploration Program, for the National Oceanic and the seafloor. Most of the living space on Earth is in Atmospheric Administration. If reproducing this the ocean. lesson, please cite NOAA as the source, and pro- Fundamental Concept f. Ocean habitats are vide the following URL: http://oceanexplorer.noaa.gov defined by environmental factors. Due to interac- tions of abiotic factors such as salinity, temperature, oxygen, pH, light, nutrients, pressure, substrate and circulation, ocean life is not evenly distributed temporally or spatially, i.e., it is “patchy.” Some regions of the ocean support more diverse and abundant life than anywhere on Earth, while much of the ocean is considered a desert.

Essential Principle 7. The ocean is largely unexplored. Fundamental Concept a. The ocean is the last and largest unexplored place on Earth – less than 5% of it has been explored. This is the great frontier for the next generation’s explorers and researchers, where they will find great opportunities for inquiry and investigation. Fundamental Concept d. New technologies, sen- sors and tools are expanding our ability to explore the ocean. Ocean scientists are relying more and more on satellites, drifters, buoys, subsea observa- tories and unmanned submersibles.

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For More Information Paula Keener-Chavis, National Education Coordinator/Marine Biologist NOAA Office of Exploration Hollings Marine Laboratory 331 Fort Johnson Road, Charleston SC 29412 843.762.8818 843.762.8737 (fax) [email protected]

 Hudson Canyon Expedition (Grades 7–9) oceanexplorer.noaa.gov Adaptations of fishes in mesopelagic and bathypelagic zones Zone Midnight or Bathypelagic Twilight or Twilight (non-migrators) Mesopelagic Zone Twilight or Twilight Mesopelagic Zone Student Handout (vertical migrators) Sunlight or Epipelagic Zone Note: These are general characteristics for fishes (not invertebrates or other marine organisms) Size Shape Musculature Eyes Coloration Bioluminescence General Characteristics of Fish in Major Ocean Zones Hudson Canyon Expedition (Grades 7–9) oceanexplorer.noaa.gov Adaptations of fishes in mesopelagic and bathypelagic zones - Zone Midnight or Bathypelagic Small size often streamlining, No globular shaped flabby muscles Weak, Eyes small or absent Black or white Bioluminescence com mon, often used to attract prey - - Twilight or Twilight (non-migrators) Mesopelagic Zone Small size Elongated and/or later ally compressed flabby muscles Weak, large, sensitive Very eyes; sometimes tubular Black or black with silver sides & belly Bioluminescence com mon, often used for counter-illumination - - Twilight or Twilight Student Handout Mesopelagic Zone (vertical migrators) Small size Elongated and/or later ally compressed Moderately strong muscles large, sensitive Very eyes Black or black with silver sides & belly Bioluminescence com mon, often used for counter-illumination - Sunlight or Epipelagic Zone Wide size range Wide Streamlined shape Strong muscles, fast swimming Large eyes countershading: Typical dark back, white or silver belly Bioluminescence rela tively uncommon Note: These are general characteristics for fishes (not invertebrates or other marine organisms) Size Shape Musculature Eyes Coloration Bioluminescence General Characteristics of Fish in Major Ocean Zones – Answer Key