Pterygophora californica

Last updated

Pterygophora californica
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Clade: Diaphoretickes
Clade: SAR
Clade: Stramenopiles
Phylum: Gyrista
Subphylum: Ochrophytina
Class: Phaeophyceae
Order: Laminariales
Family: Alariaceae
Genus: Pterygophora
Rupr., 1852
Species:
P. californica
Binomial name
Pterygophora californica
Rupr., 1852 [1]

Pterygophora californica is a large species of kelp, commonly known as stalked kelp. It is the only species in its genus Pterygophora (Ruprecht, 1852). [2] It grows in shallow water on the Pacific coast of North America where it forms part of a biodiverse community in a "kelp forest". It is sometimes also referred to as woody-stemmed kelp, walking kelp, or winged kelp.

Contents

Description

Pterygophora californica is a large brown seaweed and may grow to about three metres in height. It is attached to a rocky substrate by its holdfast and has a single, tough, woody stipe or stem up to two metres long and 2 cm (0.8 in) in diameter. It is a long-lived perennial plant which may survive for twenty-five years, [3] and annual growth rings can be seen in the stipe. There are a number of smooth blades arranged on either side of the top half of the stipe. These are sporophylls and bear reproductive organs called sporangia in which the spores are formed. The terminal blade is linear, has a midrib and is larger than the others, growing up to 90 cm (33 in) long. [4]

Distribution

Pterygophora californica is found in the sublittoral zone of the west coast of North America from Vancouver Island, British Columbia south to Bahía Rosario, [5] Baja California, Mexico at depths down to about ten metres. [6]

Biology

Reproduction in P. californica involves an alternation of generations. Microscopic zoospores are produced in the sporangia. After release, these settle on the sea bed and develop into haploid gametophytes. These produce male and female gametes the fertilisation of which results in zygote formation and the growth of the diploid sporophytes, the stipe and blades. [7] The stalked kelp has a woody stipe, and its age can be estimated (± 2 years) by counting its rings, similar to a terrestrial tree. [8]

Ecology

Pterygophora californica grows in underwater kelp forests with other brown algae including the annual bull kelp ( Nereocystis luetkeana ) and the perennial giant kelp ( Macrocystis pyrifera ). It is a dominant understory kelp species in these kelp forests, and creates a sub-surface canopy. Brown seaweeds are photosynthetic organisms and their growth is mainly restricted by the availability of light. P. californica can be restricted in its growth by shading from bull and giant kelp canopies. [9] Various algae try to get a head start by attaching themselves to P. californica well above the ocean floor. These include red algae (Rhodophyte spp.), bull kelp ( Nereocystis luetkeana ) and sea belt ( Saccharina latissima ). The most common cause of death of P. californica is being torn from the rocks during storms. This is made more likely by the drag caused by the epiphyte burden. P. californica and other Laminariales attempt to reduce their epiphytic load by periodically sloughing off their surface layers and by the production of "antifouling" substances such as phenols in their tissues. [10] The washed-up woody stipes are slow to degrade on shore, and have been found being used by bald eagles as nest material. [11]

At Race Rocks, near Vancouver Island, it was found that during the winter, the only remains of the kelp forest was the bare stipes of P. californica, the annual seaweeds having been broken down and dispersed. By mid summer however, the fast-growing N. luetkeana formed the canopy while P. californica and S. latissima formed a middle storey layer. In a research study in that location, it was found that much of the N. luetkeana was growing epiphytically on P. californica with their holdfasts attached to the blades and upper portions of the stipes. S latissima was also epiphytic but occupied the middle part of the stipe. Neither was present on the lower regions of the stipe and it was thought that this was due to grazing pressure from benthic macrofauna such as sea urchins. [12]

Herbivores feed on P. californica and other kelps, the predominant grazers being sea urchins. If the population size of these becomes too great, "barren grounds", with no large algal species, can develop and may remain in existence for years. A reduction in the number of predators or a diminution in the quantity of drift algae may encourage hungry urchins to overexploit and potentially eradicate the kelp. [7] The sea urchins Strongylocentrotus purpuratus and Strongylocentrotus droebachiensis graze on P. californica at the northern end of its range. [4]

Related Research Articles

<span class="mw-page-title-main">Kelp</span> Large brown seaweeds in the order Laminariales

Kelps are large brown algae or seaweeds that make up the order Laminariales. There are about 30 different genera. Despite its appearance, kelp is not a plant but a stramenopile, a group containing many protists.

<span class="mw-page-title-main">Brown algae</span> Large group of multicellular algae, comprising the class Phaeophyceae

Brown algae are a large group of multicellular algae comprising the class Phaeophyceae. They include many seaweeds located in colder waters of the Northern Hemisphere. Brown algae are the major seaweeds of the temperate and polar regions. Many brown algae, such as members of the order Fucales, commonly grow along rocky seashores. Most brown algae live in marine environments, where they play an important role both as food and as a potential habitat. For instance, Macrocystis, a kelp of the order Laminariales, may reach 60 m (200 ft) in length and forms prominent underwater kelp forests that contain a high level of biodiversity. Another example is Sargassum, which creates unique floating mats of seaweed in the tropical waters of the Sargasso Sea that serve as the habitats for many species. Some members of the class, such as kelps, are used by humans as food.

<i>Membranipora membranacea</i> Species of moss animal

Membranipora membranacea is a very widely distributed species of marine bryozoan known from the Atlantic and Pacific Oceans, usually in temperate zone environments. This bryozoan is a colonial organism characterized by a thin, mat-like encrustation, white to gray in color. It may be known colloquially as the coffin box, sea-mat or lacy crust bryozoan and is often abundantly found encrusting seaweeds, particularly kelps.

<span class="mw-page-title-main">Kelp forest</span> Underwater areas highly dense with kelp

Kelp forests are underwater areas with a high density of kelp, which covers a large part of the world's coastlines. Smaller areas of anchored kelp are called kelp beds. They are recognized as one of the most productive and dynamic ecosystems on Earth. Although algal kelp forest combined with coral reefs only cover 0.1% of Earth's total surface, they account for 0.9% of global primary productivity. Kelp forests occur worldwide throughout temperate and polar coastal oceans. In 2007, kelp forests were also discovered in tropical waters near Ecuador.

<i>Nereocystis</i> Genus of kelp

Nereocystis is a monotypic genus of subtidal kelp containing the species Nereocystis luetkeana. Some English names include edible kelp, bull kelp, bullwhip kelp, ribbon kelp, bladder wrack, and variations of these names. Due to the English name, bull kelp can be confused with southern bull kelps, which are found in the Southern Hemisphere. Nereocystis luetkeana forms thick beds on subtidal rocks, and is an important part of kelp forests.

<i>Laminaria</i> Genus of algae

Laminaria is a genus of brown seaweed in the order Laminariales (kelp), comprising 31 species native to the north Atlantic and northern Pacific Oceans. This economically important genus is characterized by long, leathery laminae and relatively large size. Some species are called Devil's apron, due to their shape, or sea colander, due to the perforations present on the lamina. Others are referred to as tangle. Laminaria form a habitat for many fish and invertebrates.

<span class="mw-page-title-main">Red sea urchin</span> Species of echinoderm

The red sea urchin is a sea urchin found in the northeastern Pacific Ocean from Alaska to Baja California. It lives in shallow waters from the low-tide line to greater than 280 m (920 ft) deep, and is typically found on rocky shores sheltered from extreme wave action in areas where kelp is available.

<i>Macrocystis</i> Genus of large brown algae

Macrocystis is a monospecific genus of kelp with all species now synonymous with Macrocystis pyrifera. It is commonly known as giant kelp or bladder kelp. This genus contains the largest of all the Phaeophyceae or brown algae. Macrocystis has pneumatocysts at the base of its blades. Sporophytes are perennial and the individual may live for up to three years; stipes/fronds within a whole individual undergo senescence, where each frond may persist for approximately 100 days. The genus is found widely in subtropical, temperate, and sub-Antarctic oceans of the Southern Hemisphere and in the northeast Pacific from Baja California to Sitka, Alaska. Macrocystis is often a major component of temperate kelp forests.

<i>Postelsia</i> Species of kelp

Postelsia palmaeformis, also known as the sea palm or palm seaweed, is a species of kelp and classified within brown algae. It is the only known species in the genus Postelsia. The sea palm is found along the western coast of North America, on rocky shores with constant waves. It is one of the few algae that can survive and remain erect out of the water; in fact, it spends most of its life cycle exposed to the air. It is an annual, and edible, though harvesting of the alga is discouraged due to the species' sensitivity to overharvesting.

<i>Eisenia arborea</i> Species of kelp

Eisenia arborea, or the southern sea palm, is a dominant species of kelp that is found on the western Pacific coast of North America, from Vancouver Island, Canada south to Mexico's Isla Magdalena and Baja California, as well as in Japan. They are commonly found from the midtidal areas stretching to the subtidal areas. It is an edible seaweed, a source of nutrients for grazing marine invertebrates and a source of alginic acid, a food thickener. Some of the algas have a hollow stipe above its holdfast with two branches terminating in multiple blades. Eisenia arborea is studied in order to predict environmental stress in oceans intertidal zones. Hollow stipes where present when the Eisenia arborea did not receive essential nutrients for its thalli development. Eisenia arborea with hollow stripes are believed to be evolved algae in order to increase their survival in harsh living conditions. They play a huge role in determining environmental stress.

<i>Corynactis californica</i> Species of sea anemone

Corynactis californica is a brightly colored colonial anthozoan corallimorph. Unlike the Atlantic true sea anemone, Actinia fragacea, that bears the same common name, strawberry anemone, this species is a member of the order Corallimorpharia, and is the only member found in the North American West Coast. Other common names include club-tipped anemone and strawberry corallimorpharian. The anemone can live up to at least 50 meters (160 ft) deep on vertical rock walls, and at the bottom of kelp forests. It is known to carpet the bottom of some areas, like Campbell River in British Columbia, and Monterey Bay in California.

<i>Loxechinus</i> Species of sea urchin

Loxechinus albus is an echinoderm of the family Parechinidae, native to coastal southern South America, ranging from Ecuador, along the entire coasts of Peru and Chile, to Argentina, as well as the Falkland Islands. It is the only species in the genus Loxechinus. It is known as the Chilean sea urchin or red sea urchin, but the latter name is typically used for the North Pacific Mesocentrotus franciscanus and it is not the only species of sea urchin in Chile. L. albus is found on rocky reefs and shores in the intertidal and subtidal zones to a depth of 340 m (1,120 ft).

<span class="mw-page-title-main">Seaweed</span> Macroscopic marine algae

Seaweed, or macroalgae, refers to thousands of species of macroscopic, multicellular, marine algae. The term includes some types of Rhodophyta (red), Phaeophyta (brown) and Chlorophyta (green) macroalgae. Seaweed species such as kelps provide essential nursery habitat for fisheries and other marine species and thus protect food sources; other species, such as planktonic algae, play a vital role in capturing carbon and producing at least 50% of Earth's oxygen.

<i>Saccharina latissima</i> Species of Phaeophyceae, type of kelp

Saccharina latissima is a brown alga, of the family Laminariaceae. It is known by the common names sugar kelp, sea belt, and Devil's apron, and is one of the species known to Japanese cuisine as kombu. It is found in the north Atlantic Ocean, Arctic Ocean and north Pacific Ocean. It is common along the coast of Northern Europe as far south as Galicia Spain. In North America, it is found on the East Coast down to Long Island, although historically extended down to New Jersey and on the West Coast down to the state of Washington. On the coast of Asia, it is found south to Korea and Japan.

<i>Norrisia norrisii</i> Species of gastropod

The marine snail Norrisia norrisii is a medium-sized gastropod mollusk within the family Tegulidae. It has several common names, including Norris's top snail, Norris's topsnail, norrissnail, smooth brown turban snail, or kelp snail. It was first described by G.B. Sowerby I under the name Trochiscus norrisii. It is the only species in the genus Norrisia.

<i>Laminaria hyperborea</i> Species of alga

Laminaria hyperborea is a species of large brown alga, a kelp in the family Laminariaceae, also known by the common names of tangle and cuvie. It is found in the sublittoral zone of the northern Atlantic Ocean. A variety, Laminaria hyperborea f. cucullata is known from more wave sheltered areas in Scandinavia.

<span class="mw-page-title-main">Aquaculture of giant kelp</span> Cultivation of seaweed

Aquaculture of giant kelp, Macrocystis pyrifera, is the cultivation of kelp for uses such as food, dietary supplements or potash. Giant kelp contains iodine, potassium, other minerals vitamins and carbohydrates.

<i>Alaria marginata</i> Species of seaweed

Alaria marginata, the winged kelp, is a brown alga species in the genus Alaria. It can grow up to 13 feet. Fronds are long and narrow with raised midrib and wavy edges. Each frond has two rows of several smooth, oblong, 5 inch spore-bearing blades at the base in winter.

<i>Laminaria nigripes</i> Species of seaweed

Laminaria nigripes is a species of kelp found in the North Atlantic and North Pacific within Arctic and subarctic waters including Vancouver Island, Haida Gawaii, Greenland, Iceland, Norway, Downeast Maine, and the Bay of Fundy. The species may be found exclusively in the Arctic, but frequent misidentification of samples has led to speculation and debate over whether the actual range is subarctic or Arctic. The species is commonly confused with Laminaria digitata and Laminaria hyperborea and is at risk from climate change.

References

  1. Pterygophora californica Ruprecht, 1852 World Register of Marine Species. Retrieved 2011-09-11.
  2. Pterygophora Ruprecht, 1852 World Register of Marine Species. Retrieved 2011-09-11.
  3. Lobban, Christopher S. and Michael J. Wynne (1981). The Biology of Seaweeds. Botanical Monographs Volume 17. Blackwell Scientific Publications. Oxford, UK.
  4. 1 2 Pterygophora californica (Ruprecht) RaceRocks.com. Retrieved 2011-09-11.
  5. Matson, Paul G.; Edwards, Matthew S. (June 2007). "Effects of ocean temperature on the southern range limits of two understory kelps, Pterygophora californica and Eisenia arborea, at multiple life-stages". Marine Biology. 151 (5): 1941–1949. doi:10.1007/s00227-007-0630-3. ISSN   0025-3162. S2CID   85383410.
  6. Pterygophora californica Ruprecht AlgaeBase. Retrieved 2011-09-11.
  7. 1 2 Ecology of Kelp Communities Retrieved 2011-09-12.
  8. Hymanson, Zachary P.; Reed, Daniel C.; Foster, Michael S.; Carter, John W. (1990). "The validity of using morphological characteristics as predictors of age in the kelp Pterygophora californica (Laminariales, Phaeophyta)". Marine Ecology Progress Series. 59 (3): 295–304. doi: 10.3354/meps059295 . ISSN   0171-8630. JSTOR   24842125.
  9. Watanabe, James M.; Phillips, Roger E.; Allen, Neil H.; Anderson, William A. (1992-08-21). "Physiological response of the stipitate understory kelp, Pterygophora californica Ruprecht, to shading by the giant kelp, Macrocystis pyrifera C. Agardh". Journal of Experimental Marine Biology and Ecology. 159 (2): 237–252. doi:10.1016/0022-0981(92)90039-D. ISSN   0022-0981.
  10. Lobban, Christopher S. and Paul J. Harrison (1994). Seaweed Ecology and Physiology. Cambridge University Press, Cambridge, UK.
  11. Rechsteiner, Erin U.; Wickham, Sara B.; Watson, Jane C. (May 2018). "Predator effects link ecological communities: kelp created by sea otters provides an unexpected subsidy to bald eagles". Ecosphere. 9 (5): e02271. doi: 10.1002/ecs2.2271 .
  12. The epiphytic community of Pterygophora californica: Race Rocks MPA, British Columbia Archived 2012-04-01 at the Wayback Machine Retrieved 2011-09-11.

Further reading