# Big Water Crayfish (*cambarus robustus*) The Big Water Crayfish is a fun and colorful creature that loves to hide under rocks in streams! They're great at cleaning up the water by eating dead plants and animals. - **Category:** [Invertebrate](https://www.snappit.app/explore/categories/invertebrate) - **Rarity:** Common - **Danger:** 1/5 · Very low - **Habitat:** Freshwater rivers and streams, often hiding under rocks and logs. ![Big Water Crayfish](https://commons.wikimedia.org/w/index.php?title=Special:Redirect/file/FMIB_53467_Cambarus_bartonii_robustus_%28Girard%29_Bog_River%252C_St_Lawrence_Co%252C_N_Y%252C_July%252C_1912.jpeg&width=800) Photo: E. N. Fischer, Public domain · [Wikimedia Commons](https://commons.wikimedia.org/wiki/File:FMIB_53467_Cambarus_bartonii_robustus_%28Girard%29_Bog_River%252C_St_Lawrence_Co%252C_N_Y%252C_July%252C_1912.jpeg) ## Appearance The Big Water Crayfish has a robust, dark brown to olive body, often with reddish tints, and can grow quite large. It is easily recognized by its powerful, often reddish-tipped claws that are proportionally bigger than other crayfish species. ## Taxonomy - **Kingdom:** Animalia - **Phylum:** Arthropoda - **Class:** Malacostraca - **Order:** Decapoda - **Family:** Cambaridae - **Genus:** Cambarus ## Interesting facts - Crayfish blood is colorless until it touches air, then it dramatically turns blue! - Some crayfish eat their own molted shells to regain lost calcium and nutrients! - They build elaborate burrows in mud, sometimes with multiple escape tunnels for safety! - They walk forward, but can swim backwards incredibly fast with a powerful tail flip! ## Special abilities - **Regenerative Power:** Big Water Crayfish can regrow lost claws or legs because of their incredible regenerative cells that help them recover from injuries. - **Pincer Strength:** Big Water Crayfish has strong claws that help them crush small prey, defend against predators, and even dig burrows effectively. - **Tail Flip Escape:** Big Water Crayfish can quickly arch and snap their tails because this rapid movement propels them backwards to escape danger fast. ## Measurements & details - **Length:** 10-18 cm - **Weight:** 50-150 g - **Lifespan:** 3-7 years ## Diet & Feeding This omnivore eats almost anything it finds, from plants to tiny creatures and decaying bits! - **Primary Foods:** algae, aquatic plants, insect larvae, small fish, detritus, snails - **Foraging Method:** Foraging ## Ecological connections - **Eaten by:** [North American River Otter](https://www.snappit.app/explore/north-american-river-otter) (*Lontra canadensis*) — A favorite food for river otters. - **Eaten by:** [Largemouth Bass](https://www.snappit.app/explore/largemouth-bass) (*Micropterus salmoides*) — A primary prey item for large bass. - **Eaten by:** [Raccoon](https://www.snappit.app/explore/raccoon) (*Procyon lotor*) — Raccoons often hunt them along water edges. - **Eats:** Midge larvae (*Chironomus plumosus*) — Consumes many types of aquatic insect larvae. ## Traits - [Solitary](https://www.snappit.app/explore/traits/solitary): Solitary animals live alone for most of their lives, only interacting with others for mating or parental care. - [Colorful](https://www.snappit.app/explore/traits/colorful): Colorful describes organisms or objects displaying a wide range of bright and distinct colors. - [Carnivorous](https://www.snappit.app/explore/traits/carnivorous): This trait identifies organisms whose diet consists entirely or primarily of animal tissue. - [Freshwater](https://www.snappit.app/explore/traits/freshwater): Freshwater habitats include non-saline aquatic environments such as rivers, lakes, ponds, and wetlands, vital for numerous species. - [Aquatic](https://www.snappit.app/explore/traits/aquatic): Aquatic habitats encompass environments where organisms live predominantly in water, including oceans, rivers, lakes, and wetlands. ## Collections - [Invertebrates](https://www.snappit.app/explore/collections/invertebrates) ## Safety **Danger:** 1/5 · Very low Always wash your hands after touching any wild creature. ## Frequently Asked Questions ### How to identify Big Water Crayfish? Compare body symmetry, shells, segments, legs, tentacles and how the animal moves. Invertebrates span many unrelated groups, so start with body structure. Invertebrate Identifier: upload a photo and compare the visible details. ### How long is Big Water Crayfish? 10-18 cm ### How much does Big Water Crayfish weigh? 50-150 g ### How long does Big Water Crayfish live? 3-7 years ### What does Big Water Crayfish eat? This omnivore eats almost anything it finds, from plants to tiny creatures and decaying bits! ### Where is Big Water Crayfish usually found? Freshwater rivers and streams, often hiding under rocks and logs. ### How does Big Water Crayfish hunt? Foraging ## Where to spot - [Ole Bull State Park](https://www.snappit.app/guides/places/ole-bull-state-park) — Pennsylvania, US · State Park ## More Invertebrate - [Coral](https://www.snappit.app/explore/coral) - [Crab Spider](https://www.snappit.app/explore/crab-spider) (*Mecaphesa asperata*) - [Garden Spider](https://www.snappit.app/explore/garden-spider) (*Araneus diadematus*) - [Brown Recluse Spider](https://www.snappit.app/explore/brown-recluse-spider) (*Loxosceles reclusa*) --- Source: [Big Water Crayfish: Facts & Places to See — Snappit](https://www.snappit.app/explore/big-water-crayfish)