Pacifastacus fortis
Pacifastacus fortis | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Malacostraca |
Order: | Decapoda |
Suborder: | Pleocyemata |
Family: | Astacidae |
Genus: | Pacifastacus |
Species: | P. fortis
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Binomial name | |
Pacifastacus fortis (Faxon, 1914)
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Pacifastacus fortis (known as the Shasta crayfish or placid crayfish) is an
Description and ecology
P. fortis is thick and stocky, with relatively heavy chelae. It is usually dark brown dorsally with bright orange areas on its underside. These colors aid in camouflage in its habitat. It grows about 2-4 inches long. It lives in cold, clear, rocky areas of the mountain rivers, and feeds on microbes, algae, and small animals like snails.[4] The animal requires a constant, steady, and untainted flow of fresh water to survive. P. fortis have 5 pairs of legs.[4]
With regards to life span, P. fortis tends to endure a life span of between 10 and 15 years on average.[4] Reproduction occurs once per year, typically in October, when older females produce up to 40 eggs per year and younger females produce fewer eggs. By May, most eggs will have hatched and the babies stay attached to their mother for a short duration before separating and becoming a free-willed organism P. fortis is nocturnal and remain idle behind cover for the majority of the day. They begin to leave their cover only when it is night and light is scarce. Furthermore, when possible, it prefers to live on its own without other members from its species.[4]
Predators in California include but are not limited to various species of fish, such as the brown bullhead (
Causes of endangerment
Pacifastacus fortis is listed as a
It has always had a very small native range, and that range has been significantly fragmented by such human activities as damming, mining, and agriculture. The Pit River Fish Hatchery was closed to protect this species.
Two
Its decline mimics that of its closest relative, the
P. fortis is the only native crayfish remaining in California.[9]
Conservation efforts
The Shasta crayfish was designated as a rare species by California law in 1980 and an endangered species in 1988 by the Federal Government.[10] Throughout numerous 5-year species reviews from 1988 to 2013, this endangered classification has not changed.[9] This stems from the fact that large numbers of government conservation programs have been relatively ineffective in delisting the species.[9]
A significant challenge for Shasta crayfish conservation is that while researchers know what type of food Shasta crayfish consume, their exact nutritional requirements are unknown.[10] This presents a significant challenge for long-term captive breeding programs. Furthermore, no critical habitat has been identified for this species.[10] However, there is optimism that Rock Creek could serve as a future safe haven for the Shasta crayfish.[11]
Relocation of Shasta crayfish to a new safe haven in Rock Creek
A 20-year inter-agency initiative led by the California Department of Fish and Wildlife (CDFW) found significant success in June 2019 as it relocated over 28 Shasta crayfish to a rehabilitated section of Rock Creek, Shasta County.[11] The goal of this conservation effort was to create an isolated population of Shasta crayfish that was inaccessible to the invasive signal crayfish.
As a result, this large-scale project necessitated considerable habitat modifications, such as riparian plantings and rock clusters. Likewise, a pipeline from CDFW's hatchery at Crystal Lake had to be rerouted, and an upstream diversion dam had to be removed. The Hatchery's location is optimal since it prevents signal crayfish from migrating upstream and invading Rock Creek.[11]
This restoration project was completed in collaboration with the Pacific Gas and Electric Company (PG&E), the United States Fish and Wildlife Service, CDFW, and the consulting firm Spring Rivers Ecological Sciences LLC.[11] Today, the formerly dry portion of Rock Creek flows with around 0.6 miles of cool, clear water: a suitable habitat for the Shasta crayfish.[4][11]
After completing the Rock Creek restoration, scuba divers gathered Shasta crayfish from the bottom of Crystal Lake for relocation. Crystal Lake was chosen because it contains a genetically diverse and viable population of Shasta crayfish that is most accessible to the CDFW. Following a 42-day quarantine, the divers relocated the crayfish to their new home in Rock Creek.[11]
In the long term, the progress of these crayfish will be monitored closely by the CDFW with the hope that the population can sustainably grow without intervention.
References
- ^ . Retrieved 20 November 2021.
- ^ a b "Shasta crayfish (Pacifastacus fortis)". Environmental Conservation Online System. U.S. Fish & Wildlife Service. Retrieved 7 October 2023.
- ^ 53 FR 38460
- ^ a b c d e f Shasta Crayfish 5-Year Review: Summary and Evaluation (PDF) (Report). U.S. Fish and Wildlife Service. August 2009. Archived from the original (PDF) on 2022-06-30.
- ^ "Pacifastacus fortis (Shasta crayfish)". www.cabi.org. Retrieved 2022-10-20.
- PMID 25561679.
- ^ a b "Shasta Crayfish | Encyclopedia.com". www.encyclopedia.com. Retrieved 2022-10-18.
- ^ "Pacifastacus - an overview | ScienceDirect Topics". www.sciencedirect.com. Retrieved 2022-10-18.
- ^ a b c "Pacifastacus fortis". Earth.com. Retrieved 2022-10-18.
- ^ a b c "RECOVERY PLAN for the SHASTA CRAYFISH (Pacifastacus fortis)" (PDF). U.S. Fish and Wildlife Service. U.S. Fish and Wildlife Service. August 28, 1998.
- ^ a b c d e f "Science Institute News | Endangered Shasta Crayfish Have New Refuge in Rock Creek". wildlife.ca.gov. Retrieved 2022-10-18.
External links
- B. Moose Peterson (December 17, 2009). "Species Account: Shasta Crayfish, Pacifastacus fortis" (United States Fish & Wildlife Service.
- "Recovery Plan for the Shasta Crayfish (Pacifastacus fortis)" (PDF). United States Fish & Wildlife Service. 1998.