General Characteristics of the Rocky

Name ______Name ______Date ______Block ______FIELD EXERCISE: GENERAL CHARACTERISTICS OF THE ROCKY INTERTIDAL ECOSYSTEM

A rocky shore is an ideal living laboratory to become familiar with the marine environment. It can be easily studied without any sophisticated gear or without actually getting wet. The intertidal, or littoral zone, is that part of the sea floor that is located between the highest high and lowest low tides. The many organisms that often live on the rocky intertidal are adapted to exposure to air, or emersion, as well as other types of stresses.

Objectives: Recognize the most significant physical and chemical factors affecting the rocky shore ecosystem; Become familiar with the dominant inhabitants of rocky shores; Recognize vertical zonation in rocky shore communities; Recognize some of the most obvious adaptations of marine organisms to desiccation and wave action in rocky shores; Become acquainted with tide tables.

Directions: 1. Arrive at the site to be explored at least half an hour prior to a good low tide. Watch for important characteristics of the rocky shore environment, particularly tides and wave action.. Tide level (in meters and feet) and the time of the low tide(s) can be obtained from tide tables on line or in newspapers.

2. The survey of the rocky shore should begin at the low tide level. Record the general weather conditions. If possible, bring a temperature to get the temp in a tidepool. Collect a sample of water taken directly from the tidepool and bring it back to class. If possible try to obtain a water sample with some plankton. Please do not take coral, plants or animals out of the tide pools as this is prohibited by law. Take a picture of the location where the sample was collected.

3. Observe representative organisms of each of the major zones (see the picture above). You will answer questions about the most significant adaptations of these organisms, particularly those that help them to minimize the stress of desiccation, exposure to air, and wave action.

4. Identify the major representative dominant organisms.

5. The temperature, relative height (or relationship to tide levels), and the dominant forms of life will be recorded for 3 tide pools. One of the tide pools should be as high as possible on the intertidal.

6. A minimum of 4 digital photos of the lab partners in the rocky shore survey are required in the written report. Two of the pictures must also include the lab partners in the intertidal zone. You may type your answers into this report which may be downloaded from our class website. This is the preferred method since then you can insert your digital pictures into the 4th report page and give brief descriptions or captions to your pictures. Otherwise, neatly glue or tape your pictures and captions onto an 8½ by 11 piece of paper. Field Exercise: Rocky Intertidal Ecosystem Page 1 of 4 Name ______Name ______Date ______Block ______

Location visited: ______Date of visit: ______Due date: May 1, 2008

ROCKY SHORE SURVEY: PHYSICAL FACTORS 1. Begin your survey of the rocky shore at the water level just before the time of the predicted low tide indicated by the tide table. Record the following information:

Predicted low tide (in relation to MLLW): ______m (= ______ft) Time of the low tide: ______MLLW=Mean Lower Low Water is the average low water mark for the ocean. Click here for tide tables on line (if viewed online) General weather conditions: sunlight: rain: wind : ocean conditions (wave action, spraying of waves on tide pools):

2. If possible, record the temperature of a sample of seawater taken at the water's edge and 3 tide pools (optional). Collect a water sample from one of the tide pools or from the ocean shore, using the sterile bottle and proper techniques. Do not touch the rim of the bottle and take the sample at elbow length depth if from the ocean. Mark on the bottle the date, time, and location of the sample. Take the sample within 24 of your next class day for proper water chemistry testing. o o o Open-water sample: Temperature at location: _____ C _____ F Salinity: _____ /oo o o o Tide Pool sample 1: Temperature at location: _____ C _____ F Salinity: _____ /oo o o o Tide Pool sample 2: Temperature at location: _____ C _____ F Salinity: _____ /oo o o o Tide Pool sample 3: Temperature at location: _____ C _____ F Salinity: _____ /oo (Salinity determined back in class)

3. What are some of the morphological adaptations to wave action that have been observed among the organisms? Any examples of adaptations to exposure to air (emersion)?

4. Other than the lack of oxygen dissolved in water, what kind of problems do invertebrates and seaweeds have to confront when exposed to air?

5. Have you observed any behavioral adaptations of plants / animals to wave action or to exposure to air?

6. In addition to exposure to wave action and air, are there any other challenges that organisms of the intertidal must confront? Have you observed any adaptations to these challenges?

7. How do you account for the differences in temperature, salinity, the number of species, and the abundance of organisms in each of the tide pools that were sampled?

8. Did you observe any particular patterns in the distribution of different species of organisms as you moved from the low- tide level to the highest level, one which is covered only by very high tides?

9. Why is it important to record the general weather conditions? Give some possible differences in what you have observed if the weather conditions were different from today’s weather.

Field Exercise: Rocky Intertidal Ecosystem Page 2 of 4 Names ______

VERTICAL DISTRIBUTION OF THE ROCKY SHORE COMMUNITY 10. Starting at the water's edge at the time of the low tide given in the tide table and gradually moving toward the highest levels of the shore, identify the most common species that are seen as you move up the shore. Look at the underside of rocks but be sure to turn them back to their original position. Make a sketch of the plant or animal and gives its scientific or common name. If possible, observe a tidepool in each of the three rocky shore sections or vertical zones.

Rocky shore Most common species Adaptations of these species to life on rocky shores section Sketch and name

Lower intertidal

Middle intertidal

Upper intertidal (splash zone)

Additional observations:

Field Exercise: Rocky Intertidal Ecosystem Page 3 of 4 ROCKY INTERTIDAL ECOSYSTEM 4 Digital Pictures and Captions taken on Location

Field Exercise: Rocky Intertidal Ecosystem Page 4 of 4