190 Chapter 13—Intertidal Communities
Chapter 13—Intertidal Communities
MULTIPLE CHOICE
1. The supralittoral zone is:
a.
the area below the low tide mark.
b.
the area above the high tide mark.
c.
the area between low and high tide marks.
d.
the area under the rocks.
2. Most of the animals living in the rocky intertidal are:
a.
infaunal.
b.
epifaunal.
c.
epiphytic.
d.
meiofaunal.
e.
pelagic.
3. The organisms of the intertidal are subject to daily changes in all except:
a.
exposure to air.
b.
desiccation.
c.
wind and waves.
d.
low light levels.
e.
heat.
4. During winter months in temperate environments organisms can die from:
a.
high rain fall.
b.
freezing.
c.
low sunlight.
d.
increased predation.
e.
increased pH level.
5. Lichens of the supralittoral fringe are compound associations between:
a.
algae and bacteria.
b.
fungi and bacteria.
c.
bacteria and cyanobacteria.
d.
fungi and algae.
e.
algae and cyanobacteria
6. A tar-like patch found in the upper North Atlantic supra-intertidal usually is:
a.
a lichen.
b.
a cyanobacteria.
c.
sea hair.
d.
a sponge.
e.
a seaweed.
7. Rough periwinkles that live in the splash zone use ____ for respiration.
a.
gills
b.
lungs
c.
the mantle cavity
d.
the foot
e.
the radula
8. The rough periwinkles protect exposure of eggs by
a.
producing planktonic eggs inside jelly coats.
b.
attaching gelatinous egg masses to large algae.
c.
retaining the eggs in the mantle cavity.
d.
providing a protective membrane around the eggs.
e.
dispersing them into the water column.
9. Barnacles such as Balanus are most common in the ____ zone of the rocky intertidal.
a.
upper midlittoral
b.
middle midlittoral
c.
lower midlittoral
d.
subtidal
e.
splash
10. Sea urchins living in the rocky intertidal zone use the following method to overcome wave shock:
a.
creating burrows in which they live.
b.
having a low profile.
c.
using spines to dissipate the energy of the wave.
d.
all of the above
11. Rockweeds overcome the problems of desiccation by:
a.
growing only in shaded areas.
b.
having a gelatinous covering.
c.
evaporating water from their tissues.
d.
bending with the waves.
e.
being covered with a waxy cuticle.
12. The upper limit of an organism’s distribution in the rocky intertidal is usually determined by:
a.
grazing effect.
b.
predation.
c.
pH.
d.
desiccation.
e.
competition.
13. Supralittoral isopods are
a.
predators.
b.
herbivores.
c.
detritivores.
d.
scavengers.
e.
grazers.
14. Supralittoral isopods
a.
must have some salt water cover daily.
b.
would drown if placed in water.
c.
return to the sea to lay eggs.
d.
have pseudogills.
e.
prey on barnacles.
15. On very wavy rocky shores, mussels will occupy the ____ zone without being affected too much by
predation.
a.
lower intertidal
b.
upper intertidal
c.
middle intertidal
d.
supratidal
e.
splash
16. On Pacific coasts, the population of mussels is kept in check by predation from:
a.
sea otters.
b.
sea stars.
c.
sea urchins.
d.
barnacles.
e.
supralittoral isopods.
17. The size of sediment particles on sandy beaches will influence the following characteristic of the
beach:
a.
porosity.
b.
oxygen content.
c.
food content.
d.
rate of water drainage.
e.
all of the above.
193 Chapter 13—Intertidal Communities
18. Most of the animals living in the sandy intertidal are:
a.
infaunal.
b.
epifaunal.
c.
epiphytic.
d.
planktonic.
e.
nektonic.
19. The area with the highest species diversity among the following is:
a.
rocky subtidal.
b.
sandy subtidal.
c.
sandy intertidal.
d.
rocky supratidal.
e.
splash zone.
20. ____ is common in sandy intertidal areas.
a.
Predation
b.
Algal grazing
c.
Deposit feeding
d.
Parasitism
21. An example of a filter feeder is:
a.
a mussel.
b.
a sea star.
c.
a crab.
d.
a nematode.
e.
an isopod.
22. Grain size in the intertidal is primarily determined by:
a.
wave activity.
b.
types of animals in the area.
c.
amount of sunlight.
d.
feeding types in the sediment.
e.
burrowing activity of infauna.
23. Intertidal soft bottoms are unstable due to:
a.
wave action.
b.
erosion.
c.
changing tides.
d.
currents.
e.
all of the above.
24. Ghost crabs predominate in:
a.
sandy supratidal.
b.
sandy intertidal.
c.
sandy subtidal.
d.
rocky shores.
e.
splash zones.
25. Which of the following is false about rocky shores?
a.
Mangroves are common.
b.
Silt is removed by waves.
c.
They retain finer sediments.
d.
Surf functions to oxygenate the water.
e.
Sessile organisms are common.
26. Mussels attach to the rocky shores by:
a.
byssal threads.
b.
mucous secretions.
c.
foot.
d.
calcareous shells.
e.
glue.
27. The following is not a common feeding type in rocky intertidal areas:
a.
filter feeding.
b.
scavenger.
c.
grazer.
d.
deposit feeding.
e.
carnivore.
28. Oysters dominate this rocky shore zone.
a.
The middle and low midlittoral
b.
The subtidal zone
c.
The supralittoral fringe
d.
The upper midlittoral
e.
The splash zone.
29. A tidepool exposes organisms to all the following except:
a.
desiccation.
b.
thermal stress.
c.
salinity changes.
d.
pH changes.
e.
dissolved oxygen changes.
30. Tidepool organism adaptations to changing environmental conditions are most similar to those of
animals living in the ____.
a.
supralittoral zone
b.
salt marsh
c.
sandy beach
d.
mangrove forest
e.
open ocean
31. ____ factors determine which type of algae species will predominate in tide pools in New England.
a.
Bottom-up
b.
Top-up
c.
Abiotic
d.
Biological
e.
Physical
32. The macroplants of the midlittoral temperate Pacific and Atlantic are characterized by:
a.
red algae.
b.
green algae.
c.
brown algae.
d.
seagrasses.
e.
mangals.
33. The dominant producers of the infralittoral fringe in temperate Pacific and Atlantic are the:
a.
foliose red algae.
b.
green algae.
c.
large brown algae.
d.
eelgrass.
e.
calcareous red algae.
34. The supralittoral fringe of the tropics contains all the following zones except:
a.
brown.
b.
white.
c.
gray.
d.
black.
35. The true border between land and sea in the tropics is called the ____ zone.
a.
brown
b.
white
c.
gray
d.
black
e.
yellow
36. The organism in the tropics that replaces limpets in the supralittoral fringe is
a.
turtle grass.
b.
nerites.
c.
the hermit crab.
d.
knobby periwinkle.
e.
the coconut crab.
37. The tropical supralittoral zone immersed only at the highest spring tides is the:
a.
brown.
b.
white.
c.
gray.
d.
black.
e.
yellow.
38. The upper distribution of tropical intertidal nerites can be found in the ____ zone.
a.
brown.
b.
white.
c.
gray.
d.
black.
e.
yellow
39. The tropical midlittoral fringe has two zones; they are
a.
brown and yellow.
b.
brown and pink.
c.
black and white.
d.
brown and black.
e.
pink and yellow.
40. The yellow zone in the tropical middle intertidal owes its color to:
a.
sponges.
b.
boring algae.
c.
barnacles.
d.
limpets.
e.
crabs.
41. The pink zone of the tropical middle intertdial is characterized by the widespread:
a.
irregular worm snails.
b.
coralline algae.
c.
anemones.
d.
keyhole limpets.
e.
barnacles.
42. A common organism of the temperate infralittoral fringe (lower intertidal) is called:
a.
Laminaria.
b.
Entermorpha.
c.
Ulva.
d.
lichen.
e.
giant kelp.
43. Some resident intertidal fish include all the following except.
a.
rock eels.
b.
lamprey eels.
c.
gobies.
d.
sculpins.
e.
blennies.
44. The upper sandy beach often ends:
a.
where sand dunes begin.
b.
where terrestrial vegetation begins.
c.
at the high tide line.
d.
both a and b
e.
both b and c
45. Most of the organisms of the supralittoral fringe of sandy beach cope by:
a.
moving out of the area during low tide.
b.
closing their shells.
c.
living in permanent or semi-permanent tubes and burrows.
d.
tolerating desiccation.
e.
migrating into upper tidal zones.
46. Which zone does not occur in the sandy beach?
a.
resurgence
b.
drying sand
c.
saturation
d.
retention
e.
maintenance
47. Primary production in the sandy beach is primarily by:
a.
seagrasses.
b.
diatoms.
c.
dinoflagelletes.
d.
mangals.
e.
both b and c
48. The zone that is exposed only during spring tides is called:
a.
lower intertidal.
b.
subtidal.
c.
Laminaria.
d.
seagrass.
e.
splash.
49. On both the eastern and western coasts of the USA, the subtidal zone contains very productive
a.
seagrass meadows.
b.
Laminaria seaweeds.
c.
Ulva flats.
d.
both a and b
e.
both b and c
TRUE/FALSE
50. Sessile organisms predominate on sandy/muddy subtidal habitats.
51. Sea stars are not sensitive to desiccation and hence are found in the high intertidal.
52. Zonation on a rocky intertidal zone refers to the distribution of different kinds of rocks from one area
to the next.
53. Animals living in the supralittoral fringe must be able to deal with the force of wave shock.
54. Mussels outcompete barnacles for space in the middle intertidal zone of the temperate rocky intertidal.
55. Tide pools offer refuge to intertidal animals because they are not subject to wild fluctuations in
temperature and salinity.
56. The pH of a tide pool can change dramatically over short time periods.
57. Barnacles are more adept than mussels at withstanding the effect of desiccation.
58. Beaches with heavy wave action tend to have finer sand particles and are flat.
59. Unlike rocky beaches, sandy beaches have vertical zonation of organisms that live in the sediment.
60. Coquinas are carried up the beach for filter feeding by the waves.
61. Space is not a limiting factor on a rocky intertidal beach.
MATCHING
Match the zone with those it is most closely associated with in the Stephensons’ classification system.
a.
intertidal zone
b.
maritime zone
c.
splash zone
62. Supralittoral fringe
63. Supralittoral
64. Midlittoral
Match the organism with the most closely associated tidal zone.
a.
acorn barnacles
b.
mussels
c.
periwinkles
65. Supralittoral fringe
66. Upper midlittoral
67. Middle zone
Match the plant with the zone it is most closely associated with.
a.
Laminaria
b.
Lichens
c.
Rockweeds
68. Midlittoral
69. Supralittoral fringe
70. Infralittoral fringe
200 Chapter 13—Intertidal Communities
Match the species with the zone it is most closely associated with.
a.
Fuzzy chiton
b.
Knobby periwinkle
c.
Nerites
71. White zone
72. Gray zone
73. Black zone
Match the algae with the zone it is most closely associated with.
a.
coralline algae
b.
boring algae
c.
Sargassum
74. Yellow Zone
75. Pink Zone
76. Infralittoral fringe
Match the sandy beach characteristic with the term.
a.
surf zone
b.
lacks a surf zone
c.
the water flowing back down the beach
d.
the water running up the beach
77. Swash
78. Backwash
79. Dissipative beach
80. Reflective beach
Match the wave action with the sandy beach exposure level.
a.
moderate
b.
none
c.
low
d.
high
201 Chapter 13—Intertidal Communities
81. Exposed
82. Semi-exposed
83. Protected
84. Very Protected
Match the wave type with the sandy beach exposure level.
a.
plunging, surging
b.
none
c.
spilling
85. Exposed
86. Semi-Exposed
87. Protected
Match the moisture source with the vertical sandy beach zone during low tide.
a.
low tide water retained
b.
continuous water
c.
due to capillary action of water
88. Retention
89. Resurgence
90. Saturation
Match the food source with the organism.
a.
bivalves
b.
plankton
c.
meiofauna
d.
detritus
91. Mole crab
92. Moon snail
93. Lugworm
94. Sand dollar
ESSAY
95. List the zones that comprise rocky shores. Which of the zones would you expect to have the highest
species diversity and which would have the lowest species diversity? Explain your answer.
96. List the zones that comprise the sandy shores. Which zone has the highest diversity and which has the
lowest? Explain your answer.
97. Describe what constitutes a lichen. How do they obtain their nutrition? Where are they usually found
in the rocky intertidal?
98. List at least 3 adaptations of rocky intertidal animals to resist desiccation.
99. How do intertidal brown algae compete with barnacles and mussels for space?
100. Even though rocky shores are subject to some of the same abiotic factors as sandy beaches, such as
changes in temperature and salinity, the species diversity is much higher in the former than the latter.
What other variables do you think contribute to this high species diversity in the rocky intertidal?
101. What are at least 3 adaptations that rocky intertidal organisms have for withstanding wave shock?
102. Compare the sandy intertidal and rocky intertidal with respect to the types of feeding exhibited by the
animals living in those areas.
204 Chapter 13—Intertidal Communities
103. The base of the food web in sandy intertidal areas exposed to wave action is detritus, not algae. What
prevents seaweed from having the role of primary producer in this habitat?
104. How does the introduction of predators to a habitat decrease the effects of competition between two
other species?