Introduction to Rocky Intertidal Monitoring

Transcription

1 Dear Teachers: This document serves as your guide to giving the LiMPETS Rocky Intertidal Monitoring training in the classroom. The presentation is broken up into two Prezis: Introduction to Rocky Intertidal Monitoring and Identifying Intertidal Species. This script has ways to make the presentation more engaging with Key Questions (light blue boxes) to ask your students and Quizzes (light yellow boxes). Have fun! Introduction to Rocky Intertidal Monitoring For our upcoming trip to collect scientific data, you will be marine scientists. LiMPETS stands for Long-Term Monitoring Program and Experiential Training for Students. This means that you are going to participate in an ongoing scientific study tracking the environment that teaches scientific data collection to you! This monitoring project was created in partnership with the National Marine Sanctuaries in California. What is a National Marine Sanctuary? Why do scientists want to monitor the California coast? What is a baseline? Like a National Park in the ocean. It is a protected area to limit human disturbance like oil drilling and pollution - to preserve the natural resources and protect the marine organisms. There are 13 sanctuaries and 1 US Monument in the US waters. We have 4 Sanctuaries in California. California is a very biologically rich area with many animals and habitats to protect: Deep-water currents cause upwelling which brings nutrient-rich water to surface waters Whales migration routes White sharks Fascinating deep-sea organisms Amazing coastline! So who monitors the coast for these changes? You! LiMPETS is a state-wide program that monitors the California coast. There are over 5,000 students up and down the coast of California that participate in this program. Why monitor? Establishing a baseline: if we understand what is normal in a system, we can then begin to identify trends that could be a result of destructive human activities, like trampling, harvesting, pollution, and climate change. 1. In the event of an oil spill, long-term data can provide important baseline information to assess impacts to the coast from oil. 2. Climate change is a big concern for our oceans and coasts. Climate change is the warming of our planet due to increased CO2 in our atmosphere. This also affects the ocean! Changes like: Greater Farallones Association Created by: Monika Krach Page 1 of 11

2 Sea-level rise Sea-surface temperature Ocean acidification (change in ocean chemistry from increased carbon dioxide in the atmosphere). Ocean acidification makes it very hard for some animals like snails and mussels to grow shells. What is the rocky intertidal? The rocky intertidal is the area between the highest reach of the tides and the lowest reach of the tides on the rocky coast. Tides are an important factor of the intertidal. Along our coast, we have a mix semi-diurnal tide; there are two low tides and two high tides daily. When we are planning our monitoring trip, we go at very low tide to fully explore the rocky shores. Zonation: Because organisms can tolerate different amounts of wave shock and air exposure, there is distinct zonation within the intertidal. High zone: small, shelled animals like limpets and barnacles can withstand long periods of exposure to air and therefore live in the high-tide zone Mid zone: Mussels inhabit the mid-tide zone and have adapted to withstand intense wave action by holding themselves the rocks. Low zone: soft bodied animals like sea anemones and sea stars inhabit the low-tide zone. Given the changing tides, the intertidal is a tough place to live. Challenges in the rocky intertidal include: desiccation (drying out) wave action and sand scour temperature changes predation competition What is zonation? What challenges do rocky intertidal organisms face? What adaptations do organisms have to survive in the rocky intertidal? Monitoring Methods At each of our LiMPETS sites, the algae and invertebrates are monitored in a couple of ways. Equipment needed for monitoring: transect tape for setting up your monitoring area quadrat for counting organisms datasheet to record your data field guide to help you identify organisms How do scientists study zonation over a long time period? Why does LiMPETS count squares in quadrats for some organisms like algae? Greater Farallones Association Created by: Monika Krach Page 2 of 11

3 Vertical Transect: A vertical transect is a line along which data is collected that stretches from the high intertidal to the low intertidal. We use bolts to ensure that we revisit the same spot each time we monitor. Monitoring takes place at in quadrats at regular intervals along the transect. Random Quadrats in a Permanent Area: quadrats within a permanent area of the reef. We treat a large flat area of the rocky intertidal like a coordinate plane, with an x and y axis, and we put our quardrats down at a few random coordinates to estimate abundance and biodiversity for the whole area. Total Counts: Monitor invertebrates like sea stars in a defined area that we go out to every time we monitor. We detect changes in abundance over time. Dear Teachers: Now open the next presentation, RIM Part 2: Identifying Intertidal Species Prezi. Greater Farallones Association Created by: Monika Krach Page 3 of 11

4 Dear Teachers: For this script, the major identifying features are bulleted. If your students are using the ID Notes Handout, the answers are highlight in yellow on this script. If you have time, you can also tell your students the fun facts, why monitor, and more info listed in aqua. Identifying Animals Anemones Giant green anemones and sunburst anemones Both are larger than 5 cm (2 in) in diameter and green The giant green does not have defined radiating lines on its oral disk. The sunburst anemone has radiating lines on its oral disk. What if the anemones is closed? The base, or attachment to the rock, is flared on giant greens Sunbursts have big tubercules on the outside giving them the texture of pickle. Giant greens have the texture of the outside of an avocado. Aggregating anemones: These anemones are smaller than the others, and are the most abundant Smaller than 5 cm (2 inches) in diameter, green-colored body. They often cover themselves with small shells and sand. Can form dense aggregations. What are the differences between giant green and sunburst anemones? Why do anemones cover themselves in shells and sand? Fun fact: Individuals in groups are clones and are completely identical to one another. Quiz 1 A. sunburst B. giant green C. giant green D. sunburst Mollusks Sea mussels: Bivalve mollusks with two shells. Shell blue and black in color. Can form dense "beds." More info: The California sea mussel can form beds that extend from the mid-tide zone to the low tide zone in some areas. The chief enemies What adaptations do mollusks have to withstand wave action? What adaptations do these animals have to defend against predators? Greater Farallones Association Created by: Monika Krach Page 4 of 11

5 of these large mussels are sea stars, but humans also harvest mussels sometimes in large quantities. Chitons: They are oval in shape and have 8 separate, overlapping plates and usually a fleshy skirt They can be many different colors Easily overlooked because they are small and well camouflaged. Limpets: Snail-like mollusk with one shell. Shell is cone-shaped or flat. They have the profile of a mountain. Their shells can be different sizes, colors and different textures (smooth or ribbed). Whelks: The coiled shells can be lots of different colors. Both ends of the shells are pointed. This is an important characteristic. Fun fact: Whelks are predators that feed on other snails and barnacles, feeding by drilling holes with their radula into the shells of mussels, barnacles, and limpets. Turban snails Color deep purple, black, or brown with a copper-colored top. Shell is smooth, with a round-topped shell that is usually brown or black in color sometimes with a copper-colored top. More info: Turban snails are one of the most common snails along the coast and are very abundant in the high and mid tide zone of the rocky intertidal. These snails are herbivores that graze on algae. Periwinkles: their shells have only 1 point. We do NOT monitor periwinkles. Quiz 2 A. mussels B. turban snail C. limpet D. whelk Quiz 3 A. whelk B. mussel C. limpet D. turban snail Arthropoda Hermit crabs Always check for hermit crabs! Hermit crabs live in snail shells. You will have to check each shell to see if it is a snail or a crab. Be sure to be gentle while picking up the shells and return them back where you found them. Common acorn barnacles: Very small (can be as small as a sesame seed). Greater Farallones Association Created by: Monika Krach Page 5 of 11

6 They are abundant in the high zone Usually found in groups. Barnacles have the profiles of volcanoes. More info: Barnacles are related to shrimp and crabs. Unlike most of their relatives, barnacles are usually glued to a rocky surface. When identifying, how are limpets and acorn barnacles different? Pink acorn barnacles Bigger than the acorn barnacles (about the size of grape) Usually found growing as solitary individuals rather than in groups These barnacles look like pink volcanoes that have a thatched-roof structure. Fun fact: These barnacles may live as long as 15 years and may be sensitive to pollution from sewage spills. Why monitor: These barnacles are predicted to shift due to climate change. Leaf barnacles: These barnacles are usually found in tightly clustered groups, often around clusters of sea mussels, in the mid tide zone. They have a dark brown fleshy neck Topped with small white plates. Why monitor: These barnacles are sensitive to oil pollution. Quiz 4 A. common acorn barnacle B. hermit crab C. pink acorn barnacle D. leaf barnacles and mussels Echinoderms Ochre sea stars Orange, brown or purple in color Have white spines that form a star-shape in the center. Why monitor: This species of sea stars is often considered a keystone species in many intertidal regions. It feeds mainly on mussels but will also feed on barnacles, snails, limpets, and chitons. Adult ochre sea stars have few predators, but may be eaten by sea otters and gulls. Sea star wasting: Over the past few years, there was a dramatic drop in the population due to a wasting syndrome. Scientist have identified a virus that sometimes leads to the wasting, but why certain sea stars are more susceptible than others is still being investigated. Purple sea urchin They are purple and covered with spines. Commonly inhabit rounded burrows or depressions in rocks. Juveniles are green. Greater Farallones Association Created by: Monika Krach Page 6 of 11

7 Fun fact: Most common in the low-tide zone on rocky shores, these urchins often live in protective cups and cavities in the rock that the growing urchins enlarge with their teeth and spines. Worms Honeycomb tube worms Worms that live in tubes of cemented sand grains. Tubes often found in large masses and looks like sand glued together. Fun fact: Worms use mucus to collect the sand grains and glue them together, forming a tunnel around its body. The worm only comes out of its home during high tide to feed. Quiz 5 A. purple sea urchin B. honeycomb tube worm C. aggregating anemones D. leaf barnacles Identifying Algae There are 3 groups of algae, which are in the kingdom Protista. Like plants, they use photosynthesis to make energy. They are classified by their chloroplasts and accessories pigments: green, red, and brown algae. Keep in mind that the colors of different species of algae are incredibly varied. The browns don t always look brown and the reds don t always look red. Green Algae Green pin-cushion alga Looks like little tufts of astroturf or moss. Bright green and spongy Sometimes grows between tiny cracks in the rocks. Sometimes if can feel like cotton balls What do algae need for photosynthesis? Why is sea lettuce so thin? Sea lettuce Bright green, oval-shaped blades. The blades are very thin, almost transparent 1-2 cells thick. Fun fact: Like lettuce, it can be eaten in soups and salads. This species is often used as an indicator of high disturbance, such as trampling. Greater Farallones Association Created by: Monika Krach Page 7 of 11

8 Surfgrass It is NOT algae but a true plant. Leaves are narrow and long, bright green. It is found in the low-tide zone and often in channels. Fun fact: It is a flowering grass, a monocot that has roots. In fact, it is the only true plant found in the rocky intertidal. Surfgrasses are sensitive to sewage and oil pollution. Brown Algae Rockweeds Olive green to tan in color. Flattened body, WIDE blades with distinct midrib Rockweeds have dichotomous branching - branching that splits into 2 (like a peace sign). Becomes darker, shriveled when dried out. Fun fact: To prevent drying out, rockweeds secrete a thick mucus coating that inhibits water loss. What adaptations do rockweeds have to prevent desiccation? What is dichotomous branching? More info: Many invertebrates make their homes under rockweeds at low tide. The fronds trap moisture and provide protection against the sun and wind. Quiz 6 A. green pin cushion B. sea lettuce C. rockweed Red Algae Stunted turkish towel Dark red to purplish-black blades that split near their ends (dichotomous divided blades). Sometimes they can be covered with bumps (which are reproductive structures). Fun fact: It is also called the cat s tongue because it is so rough and bumpy. Iridescent algae Large, oval shaped blades and can appear dark-purple, greenish, or brown. Can have reproductive bumps on blades (seasonally). Touch it and pull it gently, the blade should bounce back like a rubber band. Fun fact: The light provide this algae s surface with its brilliant iridescence (sometimes looks like a rainbow), but this algae doesn t always shine. Scouring pad algae Short, bushy clumps that are dark reddish-brown in color. Greater Farallones Association Created by: Monika Krach Page 8 of 11

9 Branches covered with short spines. Feels rough and dry, not slimy or smooth. Why monitor: This one of the most common algae in central California in the high intertidal. This algae is important because it provides habitat for many small organisms. Quiz 7 A. stunted Turkish towel B. scouring pad C. rockweed D. stunted Turkish towel Coralline algae Encrusting coralline algae which looks like pink, white, or gray paint spilled on a rock. Crusts may be thin or thick and produce knobby protuberances. Upright coralline algae, the branching form with calcified cell walls. It can be segmented or bushy. Sometimes it can seem crunchy to the touch. More info: Sea urchins, limpets, and chitons feed on coralline algae. Tar spot Black crust on rock, looks like tar. Feels like wet leather. Tar spot looks like spilled black or brown paint on rocks More info: It is actually the spore-producing phase of the stunted Turkish towel and others. Whether it is a crust or blade depends on conditions like temperature and photoperiod; warm temperature and long day lengths leads to the crust form. Quiz 8 A. stunted Turkish towel B. coralline algae C. iridescent algae D. rockweed Record your data Here is what your datasheet looks like when you are doing a quadrat. We estimate abundance of organisms using two methods. 1. For species that are easy to count, in the top section of the datasheet, we count every individual within the large square. 2. In the bottom section of the datasheet, for the algae and potentially very abundant animals, like barnacles and mussels, you will count the number of squares that have any portion of an alga or animal attached in that square. Not every organism will be in the quadrat. If you don t find any, write 0. And, there will be organisms that are in the quadrat but are not listed on your datasheet! What To Expect: Wear lots of layered clothing and shoes that you wouldn t mind getting a little wet or dirty. Greater Farallones Association Created by: Monika Krach Page 9 of 11

10 Try it: How would we count mussels in this quadrat? Mussels are counted by squares, not individuals, so counts will be between 0 and 25 squares. Only count the squares where the mussel is ATTACHED to the rock. For this example, we have 23 squares. Dear Teacher: if you have 15 or more minutes left in your class, do the photoquadrat activity. If you have less than 15 minutes, do the photoquadrat activity another day and go to the next slide for more quizzing! Photoquadrat Activity 1. Divide class into groups of 2 4 students each. 2. Give each group one set of the materials: photo, quadrat, data sheet and Photo ID Guide. Students can work at their desks or you may wish to set up a mock transect by stretching a meter tape along the floor and placing photos over the transect location (in meters, written on the upper corner of the photos). 3. Review the two ways to conduct counts. The algae and invertebrates listed in the first box on the data sheet are discrete and easy to count; students should therefore count the total number of individuals that they can find within the quadrat. The organisms listed in the lower box on the data sheet are more difficult to count. They may grow in continuous sheets or may be clumped closely together (e.g. most algae, aggregating anemones, etc.). Students will count the number of small squares within the large quadrat that contain any ATTACHED portion of the alga or animal (total # possible = 25). 4. Each group should choose one person to record the data on the data sheet. The other students in the group will be counting organisms within the quadrat. Start at the top of the data sheet! FAQs What if I find an animal or alga that is NOT on the LiMPETS list? We do not monitor everything. You will see many things in the intertidal that we did not learn about today. Why do you monitor these specific species? We monitor certain species, because over time, their abundance (or absence!) tells us something. For example, surfgrasses are sensitive to pollution so a large decline in the population may indicate a pollution event. You can go to to see why we monitor each species. Greater Farallones Association Created by: Monika Krach Page 10 of 11

11 Can I touch things in the intertidal? Yes! In fact, some of these organisms need to be identified with touch: Scouring pad Iridescent algae Tarspot algae Honeycomb tube worms Aggregating anemones covered with sand What about bare rock and sand? LiMPETS keeps track of bare rock and loose sand. Bare rock is available substrate for an animal or alga to settle. Loose sand indicates sand transport which might scour the intertidal removing algae. What about trampling? Animals and algae in the mid and high zone are well adapted to pounding waves. Compared to strong waves, a human foot does very little to damage the organisms. However, animals and algae in the low zone do not have adaptations to deal with someone walking on them. Hardshelled individuals like barnacles, limpets, and snails are easily crushed. Be cautious. While you can walk on mussels beds, do not walk on soft bodied animals. Note: There are two special organisms that we did not cover in the presentation. LiMPETS only monitors them at a few sites. Ask your LiMPETS coordinator. Abalone: Shell is shield-like, smooth, and dark blue, dark green, or almost black in color. Shell has a line of holes used for ventilation. Tentacles are black. Why monitor: Abalone populations have plummeted because of abalone harvest by humans. Black abalone is on the endangered species list. Abalone are broadcast spawners, so they need to be close to one another to reproduce. So the more that are collected, the more trouble they have reproducing. Owl limpets: Big limpet greater than 2.5 cm (1 in). Shell is oval-shaped with an off-set apex. Shell surface often rough with a darker rim. Why monitor: Owl limpets are harvested by humans. The owl limpet is a sequential hermaphrodite, which means that they begin their lives as males, and as they grow, they eventually turn into females. Since humans collect the biggest ones, the owl limpet population sometimes doesn t have enough females. Greater Farallones Association Created by: Monika Krach Page 11 of 11