CEDO FIELDTRIP INFORMATION, FEB. 28–MAR. 2, 2003

Thursday, Feb. 27 PM: Nan _________________Katie ________________
Friday, Feb. 28, Science Building: 206-6668
Friday-Sunday, Feb. 28-Mar. 2, CEDO: 011-52-638-20113

Instructors:      Nan Schmidt and Katie Iverson
Additional Instructors: Ralph Bonati and Scottie Henderson
CEDO Directors: Peggy Turk-Boyer and Rick Boyer
Pima Field Assistants: Mandi Boykin, Andrew Allen, Autumn Carey

Friday Feb. 28       Meet at Pima West, rm 133, Science blg. 8:40 am
                     Arrive, Orientation to CEDO
                     Early group dinner in town              3:30-5:00pm
                     Introduction to Tidepooling              6:00pm-8:30pm
                     Slide show #1: Intro to Northern
                       Gulf of California                     8:30 pm
Saturday Mar. 1      Wake up/breakfast                        6:00 am
                     Biodiversity Transects in Intertidal     7:00-9:30 am
                     Free Time/breakfast                      9:30-10:30 am
                     Work on Group Projects                   10:30am-12:00 pm
                     Lunch/Aquarium/Snorkeling/Beachwalk      12:00-4:00 pm
                     Work on Group Projects                   4:00 pm-5:00 pm
                     Dinner at CEDO                           5:30 pm
                     Tidepool Treasure Hunt!                  6:30-8:30 pm
                     Slide show #2: Marine Mammals of Gulf    8:30 pm
Sunday Mar. 2        Wake up/Breakfast                        7:00 am
                     Estero Fieldtrip                         8:00-10:30 am
                     Group Project Presentations              10:30am-12:00 pm
                     Clean CEDO, pack, etc.                   12:00-1:00 pm
                     Return to Tucson                         approx. 6-7:00 pm

You must bring proof of Citizenship (1. Passport, 2. Birth Certificate and Driver's
License or 3. Affidavit of Citizenship with photo ID) to obtain a tourist card (visa).
You need to bring food supplies, personal gear and money, and school supplies:

Food Supplies
You will need to bring food for breakfast on Saturday and Sunday mornings at
CEDO and for lunch in the vans on Friday and Sunday. For lunch on Saturday and
dinner on Friday, you will have the choice of bringing food to eat or going out to eat
in the town of Puerto Peñasco. Dinner Sat. night will be provided by CEDO. CEDO
has a full kitchen, to which we will have access. Our only obligation is to clean up
after ourselves.

Personal Gear and Money
You will need to bring clothing and a sleeping bag. Plan on warm/hot days and
cool/cold nights. Bring clothing that you do not mind getting dirty and wet. It is
especially important that you bring shoes that you can get wet and muddy—Scuba
booties and other water shoes are especially good for this. Please try very hard
NOT to bring extra or unnecessary clothing and personal items because space will
be limited in the vans. Bring a flashlight (waterproof or underwater suggested)
and extra batteries for tidepooling at night. Past students have found that a head
lantern work very well for doing the tidepool activities. And, of course, bring
sunscreen, a hat, a water bottle, etc. Bring a watch or an alarm clock!
CEDO has a bath house with showers and bathroom facilities, but because water is
expensive and in short supply, we will make every effort to conserve water while we
are visiting. You may bring biodegradable soap for ocean showers/bathing if you so
choose (herbal essence or ocean soap work well).
You will need to bring some cash for meals (if you plan on eating out) and if you
want to buy anything from CEDO’s gift shop. There are ATMs in Puerto Peñasco
but they only give out cash in pesos. Many restaurants take credit cards and
American money, but not all.

School Supplies
Please bring with you a notebook, pens, and pencils so that you can take notes and
complete assignments.

                                 CHECK LIST

___   proof of citizenship                  ___     sunscreen
___   clipboard                             ___     hat/visor
___   pencil(s) and pens                    ___     sunglasses
___   daypack for fieldtrips                ___     insect repellent*
___   warm clothes (layers)                 ___     snorkeling gear*
___   jacket/windbreaker                    ___     binoculars*
___   bathing suit*                         ___     cooler*
___   water shoes                           ___     water bottle
___   second (“dry”) pair of shoes          ___     lunch for Friday, to be eaten in
___   trash bag for your dirty clothes              the vans
___   alarm clock or watch with alarm       ___     breakfast for Sat. and Sun.
___   flashlight and extra batteries        ___     lunch for Sunday, to be eaten in
                                                    the vans
___   sleeping bag
                                            ___     snacks
___   pillow
                                            ___     sodas*
___   gloves*
                                            ___     your brain
___   camera*
                                            ___     your common sense
___   towel
                                            ___     your patience
___   biodegradable soap/shampoo
                                            ___     some cash for snacks or gifts
___   toothbrush/paste

                                 * optional items

                                Student Contract
                        Bio 296: Marine Biology Fieldtrip
                        Fri. Feb. 28 – Sun. Mar. 2, 2003
      There will be a number of activities on the fieldtrip. Most will be required,
but some will be optional (some will be optional with bonus points). You are
expected to be on time, courteous, and attentive for all activities; remember
that our time this weekend is limited.
      By initialing the following, I agree to undertake the following tasks and
assignments to the best of my ability. I understand that my grade in Bio 296 will
be determined by my willing participation in and successful completion of these
tasks and assignments.
_____        introduction to tide pooling, Friday night
_____        estero excursion, either Sat. or Sun. morning
_____        intertidal biodiversity transect, either Sat. or Sun. morning
_____        Introduction to Northern Gulf of California slide show, Fri. night
_____        Marine Mammal slide show, Sat. night
_____        Marine Invertebrates of the Intertidal Treasure Hunt, Sat. night

      In addition, by initialing the following, I agree to abide by these rules while
on the Bio 296 fieldtrip.
_____        not to smoke in the vans, on the fieldtrips, or within the CEDO
_____        to dispose of all cigarette butts properly by throwing them in the
_____        to leave the CEDO facility only on authorized excursions
_____        to follow all rules, laws, and regulations of Pima Community College
             (e.g., no illegal activities, no unauthorized consumption of alcoholic
             beverages, etc.)

____________________________ _________________________
print name                                     sign name


The Sea of Cortés is geographically known as el Golfo de California (the Gulf of
California), a narrow gulf of the eastern tropical Pacific, about 750 miles long and
an average of 95 miles wide. The northern extension of this Mexican sea lies about
100 km (60 miles) from the border of the state of Arizona. It intrudes into the
Sonoran desert, and the hot, and climate of the southwest has turned this sea into
a large evaporation basin with salinities and sea surface temperatures markedly
higher than the eastern Pacific ocean waters. The Baja California peninsula
protects the Gulf of California from the swells of the Pacific and the cool, moist
breezes generated by the California current.
Its great tides in the northernmost region (>10 m) are second in magnitude only to
the tides of the Bay of Fundy in Newfoundland. It is a subtropical sea with a great
diversity of habitats from shallow mud flats to deep ocean basins. Its warm waters
are home to a rich abundance of plants and animals from the huge blue whale to
thousands of species of plankton, sea weeds, invertebrates and fishes, including an
endangered fish (the totoaba) and a porpoise (vaquita).
The coquina limestone beachrock reef of the Puerto Peñasco area (often referred
to as "Rocky Point") provides an ideal natural laboratory for students to study
intertidal ecology. University of Arizona graduate students have conducted
research here for several theses and dissertations and undergraduate classes in
marine biology visit these rocky intertidal habitats throughout the year, coming
not only from the Tucson but also from high schools and colleges in Arizona, Utah,
New Mexico, Texas, and California.
The great tide range exposes a 100-meter band of rocky sea floor during the new
and full moon phases, enabling students and naturalists to easily observe and study
marine life in their natural habitats. Visitors to Puerto Peñasco are sure to see
shrimp boats in great abundance. Shrimp is the chief fishery of the Gulf, and the
ships trawl for penaeid shrimp. The shrimping industry, with nearly all of its
product exported to the United States, built the town of Puerto Peñasco. In the
early 1990's a major crash in the yield of shrimp drastically reduced the shrimp
fleet, causing most of the trawlers to move south. As the fleet grew in size to
about 400 vessels overfishing was inevitable and this along with unacceptable
mortalities and waste of the bycatch (incidental kill) of other species of marine
life such as juvenile sport and commercial fishes, sea stars, shellfish, and
miscellaneous invertebrates, led to the declaration in 1993 of the Northern Gulf of
California as a Biosphere Reserve.

An Introduction to the Ecology of the Northern Gulf
The first major comprehensive survey of the fauna of the Gulf of California was
achieved by a marine biologist, Ed Ricketts, and a famous author, John Steinbeck,
who cruised the Gulf of California aboard the Western Flyer, a sardine boat from
Monterey, California, from March 17 to April 13, 1940. They made extensive
collections of mostly marine invertebrates as well as making observations of the
sea's marine life and its human inhabitants, combining science, philosophy and
adventure in a classic book by John Steinbeck and Ed Ricketts (1941) "The Sea of
Cortez.” One of the few invertebrates that they couldn't catch was the quick-
footed "Sally Lightfoot,” Grapsus grapsus, a large red crab that can be seen
scurrying over the surf-battered rocky shorelines throughout most of the Gulf of
California. It is but one of the many fascinating examples of the diverse life forms
that thrive in this incredible sea.
The most significant and still poorly known eco-tragedy of the Gulf of California is
the fatal interaction between a giant fish, the totoaba, Totoaba macdonaldi, and
the smallest cetacean in the world, the vaquita, Phocoena sinus. Both of these
species are on the endangered species list with the totoaba being the only Gulf of
California marine fish on the list, and the vaquita, which is a porpoise, having the
dubious distinction of being the rarest and most endangered of all marine mammals.
Both species are endemic to the Upper Gulf of California and apparently associate
with each other, feeding on similar prey, much like the association between
dolphins and yellowfin tuna in the eastern Pacific. The gill net fishery for the
totoaba which began in the 1930's devastated totoaba populations to the extent
that the fishery was closed in 1974 and the fish was listed as an endangered
species shortly after. Unfortunately, vaquita were also caught and killed by these
gill nets. Although totoaba fishing has been prohibited for over 20 years illegal
fishing still persists. Vaquita are still being killed by these gill nets and although
the total population remaining is difficult to estimate because of the secret habits
of this shy porpoise researchers fear that there may be only a few hundred
vaquitas left.
Not all catastrophic population crashes can be blamed on overfishing. The common
sun star, Heliaster kubiniji, once abundant in rocky intertidal zones in the
Northern Gulf suffered a major population crash throughout its range in the Gulf
in the summer of 1978. A disease related to abnormally warm sea surface
temperatures in 1978 killed off at least 95% of the sun star population. To this
date they have not recovered although sun stars are becoming more common in the
mid riff region where nearly constant upwelling keeps surface waters cool.

The largest sea cucumber in the Gulf of California (Isostichopus fuscus), a relative
of the sun star, is becoming scarce in certain regions, not due to temperature
changes but to over exploitation by Mexican hooka-divers. These edible sea
cucumbers are exported to the orient.
The Gulf of California supports a high diversity of colorful asteroids or seastars.
The crown-of-thorns seastar, Acanthaster ellisii, is common throughout the
warmer regions of the Gulf of California. A close relative to the notorious
Acanthaster planci who decimated much of the Great Barrier Reef, the Gulf
species also feeds on corals by everting its stomach and digesting the coral polyps
leaving the bleached skeleton behind. However, Gulf crown-of-thorns populations
have not reached epidemic proportions and this seastar is curiously rarely found on
the Gulf's only true coral reef at Cabo Pulmo.
The Gulf of California is famous for its immense schools of the scalloped
hammerhead shark, Sphraena lewini, which aggregate near offshore islands and sea
mounts. However, the shark fisheries in the Gulf are decimating several species of
shark with their gill nets, and the large schools of hammerheads that scuba divers
from throughout the world come here to see are not as common nor as large as
they once were.
The two most commonly caught "jumbo" shrimp of the Mexican fishery are: the
brown shrimp, Penaeus californiensis, and the blue shrimp, Penaeus stylirostris.
Shrimp are caught by otter trawls that are dragged over the sea floor for miles
scraping up sea life in their path. It is the most destructive method of commercial
fishing in the world since the trawls kill and waste millions of tons of marine
animals, including the juveniles of several species of commercial fishes, especially
the endangered totoaba.

Invertebrates of the Gulf of California
The Gulf of California is not noted for its coral reefs, unlike the Caribbean. More
common are patches of "soft coral" or colonial anemones such as the brown carpet
anemone, Palythoa ignota. Like true coral the polyps of this colony contain the
green zooxanthellae symbionts, which aid in the nutrition of this sessile
The samurai hydroid (Samuraia tabularasa) is related to the corals and has stinging
cells (nematocysts) on its tentacles. The samurai hydroid thrives among patches of
barnacles, clearing out its own space by stinging and eating barnacle larvae as they
try to settle and attach.
Marine invertebrates often form associations with each other that are often
mutually beneficial. The staghorn hermit crab, Manucomplanus varians, uses for its

home a "shell" consisting of the staghorn hydrocoral, Janaria mirabilis, which
protects the crab from predators with its stinging tentacles and in turn feeds on
the debris of food particles formed when the hermit crab tears apart its prey.
The Gulf of California is a paradise for shell collectors, which is sometimes
unfortunate for the mollusks that live in these shells. The tent olive, Oliva
porphyria, the world's largest olive shell with a shell length to 5 inches, is
relatively common in the Gulf. It hides its beautifully marked glossy shell of tent
markings by burrowing in the sand where it preys on smaller olives and other snails.
Dall's cone, Conus dalli, has a similar network of tent markings on its shell but is
one of the many venomous species of cones shells found in tropical waters. It uses
its venomous harpoon to spear and immobilize other mollusks, mostly small snails.
Other species, such as the purple cone, Conus purpurascens, prey on small reef
fishes. All cones are potentially dangerous to humans and one should be careful in
handling them..
Nudibranchs and slugs are snails that have evolutionary lost their hard shells. Most
are quite colorful but toxic giving them protection from predators. Examples of
these are the galactic sea slug (a nudibranch), Chromodoris galexorum, with its
brilliant scarlet splotches is only about 1.5 inches long. Another nudibranch,
Ghiselin's sea slug, Hypselodoris ghiselini, is a little larger (~3 inches) and secretes
obnoxious chemicals for defense against potential predators. In general poisonous
animals are strikingly colored, a so-called warning coloration that discourages
predators from even attempting to feed upon them..
There are about 6 common octopuses in the Gulf. The largest of these is the two-
spotted octopus, Octopus bimaculatus, which reaches nearly a half meter in length.
It is common throughout the Gulf and ranges to Panama and southern California but
is most abundant in the upper Gulf regions. Another species, the veligero octopus,
Octopus veligero, is similar in size and appearance to the two-spot but can be
recognized by its bright orange siphon and the lack of the two dark metallic-blue
ocelli characteristic of Octopus bimaculatus. Another octopus, the pigmy octopus,
Octopus digueti, lives in empty snail and clam shells in sandy bays, such as Cholla
 The Humboldt squid, Dosidicus gigas, are abundant in the Gulf of California where
they migrate to spawn and die. They grow to at least 13 feet in length and may
weigh up to 100 lb. They feed at the surface at night and will not hesitate to
attack divers that dare to swim amongst them. Their suckers are toothed so they
will cause circular abrasions on one's skin if they wrap their arms around an arm or

Fishes of the Gulf of California
The spectacular Pacific manta, Manta hamiltoni, which attains a width of 25 feet,
used to be abundant in the Gulf of California until commercial gill nets drastically
reduced their populations. An incident at Isla San Benedicto, a small oceanic island
outside the Gulf, where Mexican shark fishermen were illegally setting gill net and
killed several, large and almost tame manta rays caused the Mexican government to
pass a law forbidding the killing of mantas. Their poaching was exposed by an
organization called "Sea Watch" who reported them and secured video tapes of
their illegal activity.
The Gulf of California grunion, Leuresthes sardina, is a small slivery fish, that like
its close relative, the California grunion, has spawning runs high on the beaches of
the upper Gulf during winter and spring. The grunion is the only fish that
completely leaves the water to deposit its eggs in beach sand which is exposed for
at least 10 days between spring tides. Nighttime runs are the norm for the
California species but the Gulf species has runs both at night and during the day,
as they are responding to the seasonally changing tide patterns in the northern
The Panamic moray eel, Gymnothorax castaneus, is the largest common moray eel in
the Gulf of California (to 4 feet) can appear menacing to divers looking into
crevices. It is not aggressive but may bite if provoked. The banded cleaner goby,
Elacatinus sp., has little to fear as the moray welcomes its intrusion near its mouth
and gills as it removes bothersome crustacean parasites from these areas.
Many tropical reef fishes have juvenile phases that are colored entirely
differently from the adult. An example of this is the king angelfish, Holacanthus
passerhas very different adult and juvenile color phases. Often the young are more
brightly colored and therefore more conspicuous to predators than the adults. This
is especially true in the damsel fishes and this paradoxical reversal of color
patterns has never been adequately explained.
Most of the species of fishes in the Gulf of California are small, aquarium-sized
fishes like blennies. The signal blenny, Emblemaria hypacanthus, is one of over a
dozen species of tube blennies, so called because they live in the vacated tubes of
certain invertebrates.

Birds and Reptiles in the Gulf of California
The black sea turtle, Chelonia agassizi, is the most common large sea turtle in the
tropical eastern Pacific, although its numbers have been catastrophically reduced

by commercial fishing. Now protected, although commonly caught and sold illegally,
its biology is currently being studied
The Gulf islands provide nesting sites for a variety of seabirds, including brown
pelicans, elegant and royal terns, sea gulls, cormorants, brownfooted boobies and
the bluefooted boobies. Seabird populations are protected and several islands are
off-limits to casual visitors. Seabirds may be used as an indicator or the ecological
health of the Gulf of California because they feed on fishes, squid and plankton in
the surface waters. Currently, the seabird populations are thriving suggesting that
the productivity of the Gulf is still strong despite excessive overfishing.

Marine Mammals in the Gulf of California
California sea lion (Zalophus californianus) populations are thriving in the rich,
productive waters of the upper Gulf. They are protected and their numbers may
be approaching 30,000 despite mortalities due to entanglement in gill nets and the
pups being slaughtered for shark bait. The males set up territories beginning in
the spring and mate with their harem of females during the summer after the
females give birth. As many as 10,000 young are born each year, although natural
and fishing mortalities significantly impact that number. Gulf of California sea lions
are being monitored and studied by several U.S. and Mexican scientists.
Sometimes the surface of the Gulf is so flat that surface ripples from the activity
of animals may be seen over long distances. Whalespotting is ideal under these
conditions and the Gulf of California is an excellent site for whalewatching. Some
whales, such as the Bryde's whale, Balaenoptera edeni, can be identified by the
shape of their dorsal fin. The Bryde's whale is a medium-sized baleen whale (~20
tons) that is frequently sighted in the Gulf and is often confused with the larger
fin whale.
The fin whale, Baleaenoptera physalus, is the most common baleen whale in the Gulf
It is second only to the blue whale in size, reaching a maximum length of 85 ft and
a weight of 80 tons. This widely distributed whale appears to have a resident
population in the Gulf of California, and the best place to find them is in the mid-
riff region during the winter and spring. Fin whales have light chevron marks on the
back of the double blowhole that clearly identifies them. The fin whale is unique in
the animal kingdom by its asymmetry in lower jaw coloration. The right side of the
jaw is white whereas the left side is dark. The fin whales feeds primarily with its
right side submerged as would be predicted by this unusual form of counter
The humpback whale, Megaptera novaeangliae, is an occasional visitor to the Gulf of
California. One of the more spectacular of the great whales it is known for its

sensational breaching, lobtailing, and blowing a ring of bubbles to herd its prey of
small schooling fish. Humpback whales are more frequently spotted in the lower
Gulf of California.
Orcas, or killer whales, Orcinus orca, are associated with the cold waters of the
Pacific northwest so it seems peculiar to see them cruising in warm waters of the
Gulf of California in the summer along the and Baja California coast. However, they
are frequent visitors to this sea possibly because of rich availability of fish,
dolphins, sea lions and large baleen whales in the Gulf during all times of the year.
Pods of orcas have been observed attacking blue whales and Bryde's whales, and
recently, a whale shark in Bahia de los Angeles.

(Most of the material in this introduction was taken from the website of Dr.
Donald A. Thompson, University of Arizona, Ecology and Evolutionary Biology
Department. The URL is

                HUNT—THE SHORT FORM

Your task is to find representatives of as many of the following phyla, classes, and
groups as you possibly can. Circle each one that you find and have an instructor
initial in the space provided.


     INITIALS                            ORGANISMS CATEGORY

                         D. Chlorophyta
                         D. Phaephyta
                         D. Rhodophyta
                         P. Porifera
                         C. Anthozoa
                         C. Hydrozoa
                         P. Platyhelminthes
                         C. Polyplacophora
                         C. Gastropoda
                         C. Bivalvia
                         C. Polychaeta
                         Brachyuran crab
                         Anomuran crab
                         C. Holothuroidea
                         C. Asteroidea
                         C. Ophiuroidea
                         C. Echinoidea
                         P. Chordata

                HUNT—THE LONG FORM

Your task is to find representatives of as many of the following phyla, classes, and
groups as you possibly can. Circle each one that you find and have an instructor
initial in the space provided.
Kingdom Animalia
             Phylum Porifera
                   Encrusting sponges
_____                     Haliclona sp.        Wandering sponge
_____                     Geodia sp.                White-cored sponge
_____                     Leucetta sp.              Breadcrumb sponge
_____                     Leucosolenia sp.          Miniature finger sponge
_____                     Pseudosuberites sp.              Cratered sponge
_____                     Tedania sp.               Red-spired sponge
                   Boring sponge
_____                     Cliona sp.                Boring sponge
             Phylum Cnidaria
                   Class Anthozoa (anemones/corals)
_____                    Bunodactis sp.             Green-tentacled sticky
_____                     Bunodosoma sp.            Naked, warty anemone
_____                     Calamactis sp.            24-tentacled burrowing
_____                     Metapeachia sp.           16-tentacled burrowing
_____                     Palythoa sp.              Brown carpet anemone
_____                     Zoanthus sp.              Soft green coral
_____                     Porites sp.               Emerald coral
_____                     Muricea sp.               Rough red gorgonian
_____                     Psammogorgia sp.          Smooth red gorgonian
_____              Class Scyphozoa (jellies)
                   Class Hydrozoa (colonial hydroids/siphonophores)
_____                     Aglaophenia sp.           Ostrich plume hyroid

_____               Physalia sp.               Portugeuese man-of-war
        Phylum Platyhelminthes (flatworms)
_____               Alleena sp.                Slender gray flatworm
_____               Pseudoceros sp.            Mexican skirt dancer
_____               Stylochoplana sp.          Broad gray flatworm
_____   Phylum Nemertea (ribbon worms)
        Phylum Sipuncula
_____               Phascolosoma sp.           Peanut worm
_____   Phylum Ectoprocta (bryozoans)
        Phylum Annelida
              Class Polychaeta (marine segmented worms)
                    Bristle worms
_____               Eurythoe sp.               Fireworm
_____               Halosydna sp.              Scaleworm
                    Tube worms
_____               Bispira sp.                Banded feather duster
_____               Diopatra sp.               Shell-cementing tube worm
_____               Spirorbis sp.              Spiral tube worm
        Phylum Mollusca
              Class Polyplacophora (chitons)
_____               Chiton virgulatus          Green chiton
_____               Stenoplax conspicua        Black chiton
              Class Gastropoda (snails, nudibranchs, sea slugs, limpets and sea
_____              Acanthina angelica                Angelic tooth snail
_____              Cerithidea maxatlantica           Estero horn snail
_____              Cerithium stercusmuscarum         Mudflat horn snail
_____              Columbella sp.                    Inflated dove shell
_____              Conus sp.                         Cone shell
_____              Cypraea annettae                  Annette’s cowry
_____              Hexaplex erythrostomus            Pink murex
_____              Littorina sp.                     Periwinkle

_____        Mitrella sp.                Miter shell
_____        Muricanthus sp.             Black murex
_____        Nerita sp.                  Nerite snail
_____        Oliva sp.                   Olive snail
_____        Olivella sp.                Small olive snail
_____        Polinices sp.               Moon snail
_____        Tegula sp.                  Top shell
_____        Thais sp.                   Dogwinkle
_____        Turbo sp.                   Turban snail
_____        Turitella sp.               Tower shell
_____        Trivia sp.                  Coffee bean cowry
_____        Serpulorbis sp.             Worm shell
_____        Collisella sp.              Limpet
_____        Crepidula sp.               Slipper shell
_____        Crucibulum sp.              Cup-and-saucer shell
             Sea Slugs
_____        Berthellina ilisima         Apricot sea slug
             Sea Hares
_____        Aplysia californica         Sea hare
_____        Chromodoris norrisi         Norris’s nudibranch
_____        Tridachiella diomedea       Mexcian dancer
        Class Bivalvia (clams, oysters, mussels, and scallops)
_____         Arca pacifica              Ark shell
_____         Atrina sp.                 Pen shell
_____         Brachiodontes sp.          Seed mussel
_____         Lithophaga sp.             Boring mussel
_____         Modiolus sp.               Horse mussel
_____         Chama sp.                  Jewel box shell
_____         Chiona sp.                 Venus clam (cockle)
_____          Tagelus sp.               Jackknife clam
_____         Lima sp.                   Swimming clam

_____              Ostrea sp.                Oyster
             Class Cephalopoda (octopus, squid, cuttlefish, and Nautilus)
_____              Octopus digueti           Shell-dwelling octopus
_____              Octopus fitchi            Reef octopus
_____   Phylum Arthropoda
_____        Class Crustacea
                   Group one: amphipods/copepods/isopods
_____                                        Amphipods
_____              Tylos sp.                 Beach pill bug
_____              Lygia occidentalis        Rock scooter
                   Group two: barnacles
_____              Balanus sp.               Acorn barnacle
_____              Chthamalus anisopoma      Small barnacle
_____              Tetraclita squamosa       Thatch-roof barnacle
                   Group three: lobsters/shrimp
_____              Callianassa sp.           Ghost shrimp
_____              Lysmata californica       Red cleaner shrimp
_____              Penaeus californiensis    Brown shrimp
_____              Palaemon ritteri          Tidepool shrimp
                   Group four: brachyuran crabs (true crabs)
_____              Ala cornuta               Decorator crab
_____              Callinectes bellicosus    Swimming blue crab
_____              Epialtus sp.              Sargassum crab
_____              Eriphia squamosus         Lumpy-claw crab
_____              Pachycheles setimanus     Hairy-claw crab
_____              Pilumnus sp.              Hairy crab
_____              Uca sp.                   Fiddler crab
                   Group five: anomuran crabs (hermit crabs/porcelain
_____              Clibanarius digueti       Red-fingered hermit crab
_____              Paguristes anahuacus      White-fingered hermit crab
_____              Petrolisthes sp.          Porcelain crab
        Phylum Echinodermata

             Class Holothuroidea (sea cucumbers)
_____              Brandtothuria impatiens Bottle cucumber
_____              Isostichopus fuscus       Brown cucumber
_____              Selenkothuria lubrica     Sulfur cucumber
             Class Asteroidea (sea stars)
_____              Heliaster kubinjii        Sun star
_____              Linckia columbiae         Variable gray-red sea star
_____              Luidia phragma            Fragile sea star
_____              Othilia tenuispina        Diurnal sea star
_____              Pharia pyramidata         Blue-lined sea star
_____              Pharia pyramidata         Orange-centered sea star
             Class Ophiuroidea (brittle stars)
_____              Ophiocoma aethiops        Giant black brittle star
_____              Ophiocoma alexandri       Banded brittle star
_____              Ophioderma sp.            Smooth brittle star
_____              Ophionereis annulata      Ringed brittle star
_____              Ophiothrixs spiculata     Barb-spined brittle star
             Class Echinoidea (sea urchins and sand dollars)
_____              Echinometra vanbrunti     Common purple urchin
_____              Ecidaris thouarsii        Club-spined urchin
_____              Mellita longifissa        Delicate sand dollar
_____              Encope grandis            Giant keyhole sand dollar
_____              Encope micropora          Six-hole sand dollar
        Phylum Chordata
             Subphylum Urochordata (tunicates)
_____                                        Colonial tunicates
_____                                        Solitary tunicates
             Class Chondritchyes (bony fishes)
_____              Abudefduf troschelii      Sargeant major
_____              Girella simpliciden s     Gulf opaleye
_____              Gobiosoma chiguita        Sonora goby
_____              Urolophus halleri         Round stingray
             Class Aves

_____                                             Great blue heron
_____                                             Brown pelican
_____                                             Willet
                   Class Mammalia
_____                   Tursiops gilli            Bottlenose dolphin
_____                   Zalophus californianaus   California sea lion

Kingdom Protista
            Division Chlorophyta (green algae)
_____                   Codium sp.                Dead man’s fingers
_____                   Enteromorpha sp.          Green ribbon alga
_____                   Ulva sp.                  Sea lettuce
            Division Phaeophyta (brown algae)
_____                   Colpomenia sp.            Bubblegum alga
_____                   Cutleria sp.              Banded fan alga
_____                   Dictyota sp.              Bilobed alga
_____                   Sargassum sp.             Sargassum
            Division Rhodophyta (red algae)
_____                   Amphiroa sp.              Branched coralline alga
_____                   Gigartina sp.             Pinnate alga
_____                   Laurencia sp.             Lavender turf alga
_____                   Lithophyllum sp.          Encrusting coralline alga
_____                   Lithothamnion sp.         Knobby coralline alga
_____                   Polysiphonia sp.          Sea fur
Kingdom Plantae
            Division Tracheophyta (sea grasses/succulent halophytes)
_____                   Batis sp.                 Salt wart
_____                   Distichlis sp.            Indian wheat
_____                   Salicornia sp.            Pickleweed
_____                   Sueda sp.                 Seepweed

          Outline of Intertidal Marine Biology
Intertidal zone
  Also called the littoral zone
  The part of the sea floor that lies between the highest high and lowest low
  Unique in the marine realm b/c it is regularly exposed to air
  Emersion: being out of the water and exposed to air
  Immersion: being underwater
  What lives in the intertidal zone depends a lot on the substrate: the material
    of which the bottom is made up.
  Two substrates in the intertidal:
     Hard, rocky bottoms
     Soft bottoms
  What does the word “benthic” refer to?
     Organisms that live on the bottom
     Benthic can be divided up into
     Epifauna: organisms that live on the surface of the substrate (sand, rock,
        Many are sessile
     Infauna: organisms that burrow into the substrate
        Most are mobile
Rocky Shores
  Rocky shores usually don’t have a lot of sediment (loose sand and mud = “dirt”).
     Often are high energy -- lots of wave action
     Example: U.S. Pacific Coast
  Rocky Shores: Low Tide
     Exposure to air: varies from upper part of intertidal zone to lower part
     1. Water loss
        Dessication: drying out.
        Mechanisms to prevent dessication:
           1. run and hide some place moist
           Tide pools, cracks and crevices, seaweed beds…
           Works for mobile organisms
           Sessile organisms may only be found in moist places
           2. Clam up
           Sessile organisms with protective covering (shell)
           Clamping down -- sealing off body from air
           3. Let yourself dry out!

      Some intertidal seaweeds (like Fucus or rockweed) can withstand a 90% loss
       of water and recover fully!
2. Temperature and salinity
   In open ocean, both are very constant
   In intertidal, both fluctuate a lot
   Organisms deal with these fluctuations by using several strategies:
       1. Tolerate a wide temperature or salinity range
       2. Run and hide! Avoid the fluctuation
       3. Light color heats up less
       4. Clam up to avoid rainwater (low salinity)
3. Restriction of feeding time
   Little sediment: deposit feeders are rare
   Most sessile organisms are filter feeders
   Can only feed when tide is in!
   The higher up in the intertidal zone, the more of a problem this is
       Slow growth
4. Wave energy in the rocky intertidal
Wave shock: impact of the waves on the bottom
Varies from place to place, some places are more exposed; others are more
Mechanisms to cope with wave shock
   1. Only live in sheltered locations
   2. Sessile organisms often anchor themselves
       Seaweeds use holdfasts
       Mussels use byssal threads
   3. Mobile organisms may cling
       Gobies and clingfish has modifed pelvic fins that act like suction cups
   4. Mobile organisms may run and hide
       When the going gets tough, these guys take shelter!
The rocky intertidal is a good place to live!
   Lots of light and nutrients, lots of food for animals….
   Availability of space is most often the limiting factor for rocky intertidal
The battle for space: strategies?
   1. Get there first, when there is an open space.
   Must have an effective means of dispersal for either yourself or your offspring
   Must be good at holding on to the space or producing lots of young to disperse
     to other spaces...
   2. Take over spaces that are already occupied
       Barnacles undercut their neighbors

      Overgrow your neighbors
The battle for space: interactions?
   Competition and physical factors can interact to determine population
      Blue mussel: sheltered locations, thinner shell, attaches less strongly
      California mussel: open coast, thicker shell, attaches more strongly
      Blue mussel does fine on the open coast unless the California mussel is
      So, its distribution is determined not by physical factors (wave shock) but
        by competition with California mussel
      Ca. mussel’s thicker shell crushes it
      On the other hand, blue mussel does well in sheltered areas because it can
        tolerate a lot of silt in the water
      The Ca. mussel can’t
Vertical Zonation in the rocky intertidal
    a given species is usually not found throughout the intertidal but only within a
     particular vertical range.
   What causes it?
       Upper limit: physical factors
       Lower limit: biological factors
   three rocky intertidal zones
   1. upper intertidal:
       Seldom submerged; exposed to air most of the time
       Vertical Zonation in the rocky intertidal
       Lichens, algae, periwinkle snails, limpet snails, crabs, sea lice
       Land predators > marine predators
   2. middle intertidal:
       Submerged and uncovered by tides on a regular basis
       Upper boundary: barnacles, often 2 species
       Upper limit: exposure to air, one species tolerates it better
       Lower limit: one species outcompetes the other for space
       Lower limit: predation
       Some typical organisms:
       Mussels, barnacles, seaweeds
       Keystone predators: sea stars
       They eat barnacles
       Their presence/absence determines community structure
       Succession: patterns of regrowth after an area is disturbed
       Bacteria & algae --> seaweeds --> barnacles --> mussels
       Predators and grazers may alter this succession
   3. lower intertidal:
       Submerged most of the time

           Mostly marine predators
           Lots of seaweeds
           Lots of competition for space and for light
           Ex. green thread alga and Irish moss (really a red alga)
           Green thread alga outcompetes Irish moss in tide pools
           Unless periwinkle snails are present
           Periwinkles like to eat green thread alga, leaving Irish moss to thrive
           BUT crabs eat periwinkles
           Crabs can hide in green thread alga but not in Irish moss (where they are
             more likely to be eaten by gulls)
           This whole little story keeps a balance, with tide pools with both algae
Soft-bottom intertidal communities
    Any bottom made up of sediment (instead of rock)
       Can be sand, mud, silt, ...
    Most of East Atlantic Coast and Gulf of Mexico coast
    Also, near mouths of rivers
    soft-bottom sediments are constantly moving in response to waves and
    Few seaweeds
    Sometimes sea grasses
    No places for organisms to attach
    Most are infauna: live in the sediment
    Most are deposit feeders that extract organic material from the sediments
    What are the sediments like?
       Low energy areas have lots of mud and silt
       Higher energy areas have lots of sand
    mud and silt
       Lots of organic material for deposit feeders
       Little organic material for deposit feeders
    Problems with living in the sediment
       Oxygen availability
          Oxygen used up by
       Decomposition of organic matter
       No photosynthesis, so limited oxygen source is water in the sediment
    Anoxic: sediments with no oxygen in them
       Some bacteria can respire without using oxygen
    Anaerobic respiration

   Break down organic matter and produce hydrogen sulfide
   Black and smelly
Soft-bottom intertidal organisms have adaptation to avoid anoxic conditions
   Siphons and burrows: pump oxygen-rich water from above to the organisms
   burrows: pump oxygen-rich water from above to the organisms
   Tolerate low-oxygen conditions
Getting around in the soft bottom
   Burrowing with muscular foot (clams)
   Plough through with spines and tube feet (urchins)
   Dig with jointed appendages (amiphipods, crabs, shrimp)
   Be really small
   Soft-bottom intertidal communities
   Getting around in the soft bottom
   Be really small
   Eat their way through the sediment
       Deposit feeding
       Sea cucumbers, worms...
Eating in the soft-bottom intertidal
   Most eat detritus
      Some filter feeders
      Deposit feeders
   Some eat each other
   Scavengers (urchins, worms)


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