Full Grown Blue Crayfish: Size, Appearance, Price & More

Blue crayfish make fascinating pets, but their needs change as they mature into adulthood. This guide covers everything you need to know about full grown blue crayfish, from their size and weight to care, feeding, behavior and more.

By understanding their requirements at this stage, you can ensure your blue crayfish thrives as a full-fledged adult.

Size at Full Growth

Blue crayfish reach their full size around 9-12 months of age. Fully grown males, known as bulls, can grow up to 5-6 inches in body length from head to tail. Females, called sows, tend to be slightly smaller at 4-5 inches as adults.

Their body width also increases as they mature. Bulls attain a body width of 2-3 inches, while sows have a width of 1.5-2 inches at full size.

Weight at Full Growth

In terms of weight, adult blue crayfish range from 2-5 ounces on average. Bulls tend toward the heavier end of this spectrum at 3-5 ounces, whereas sows fall at the lighter 2-3 ounce mark when fully grown.

Appearance at Full Growth

Several distinct physical characteristics emerge as blue crayfish reach adulthood. Their claws grow significantly larger and more robust. The bull's front claws, or pincer claws, become noticeably enlarged for combat and mating. Females have smaller claws that are suited to their role as caretakers of eggs and hatchlings.

Their body coloration also changes, taking on a deeper cobalt blue hue all over as they age. White or cream-colored spots may fade away. The bull grows "shoulders" - thickened sections near the claw joints.

Overall, the adult blue crayfish has a bolder, more vivid blue shell and a well-defined, mature appearance.

Personality at Full Growth

Notably, the blue crayfish's temperament adjusts with sexual maturity. As an adult, the bull becomes more aggressive and territorial toward other male crayfish. He establishes and defends his dominance within the aquarium. Females remain generally docile unless protecting their young.

Breeding behaviors also emerge. During mating season, the bull becomes amorous and prone to chasing females. While crayfish don't form long-term social bonds, the sow does display maternal instincts by guarding her fertilized eggs.

Price

The price of blue crayfish scales up with their size at maturity. Young juveniles cost $5-10 each on average, while fully grown bulls and sows command higher $15-20 price tags. This premium pricing reflects their status as sexually mature pets.

Food/Feeding

Adult blue crayfish have larger appetites to fuel their growth. Feed fully grown individuals every other day with a varied diet including:

• Shrimp pellets or algae wafers
• Blanched vegetables like zucchini and spinach
• Protein-rich foods like bloodworms and brine shrimp
• Calcium-fortified algae tablets

You may need to supply 1-2 more feedings per week compared to juveniles. Monitor that all crayfish are eating to support their heartier nutritional needs.

Lifespan

With high-quality care, the average lifespan of blue crayfish as pets ranges from 3-5 years. However, some bulls and sows have been documented living 6-8 years or more in ideal aquarium conditions. Proper water quality upkeep and a varied, nutritious diet extending into adulthood help maximize their potential longevity.

Health at Full Growth

To maintain robust health as adults, fully grown blue crayfish require:

• Pristine water quality through regular partial water changes
• Adequate territory and hiding spaces to reduce stress
• Access to calcium-fortified foods to support shell integrity
• Monitoring for signs of shell deterioration or lethargy

Be vigilant for common ailments in mature crayfish like molting issues, shell rot, and joint infections that can plague individuals aging out of their juvenile immune defenses.

Care and Nutritional Needs at Full Growth

Several changes to accomodate an adult blue crayfish's care needs:

• Provide a 20-30 gallon aquarium minimum for one bull or sow
• Maintain stable water conditions with a filter and weekly 25% water changes
• Supply hiding shelters, plants, and substrate for burrowing and molting comfort
• Test water parameters regularly to ensure optimal habitat
• Feed a protein-dense, nutrient-balanced diet tailored for adult crayfish

Careful maintenance is crucial as their health needs intensify and tank space becomes more important at this advanced growth phase.

Costing

Estimating long-term costs of keeping full grown blue crayfish involves factoring:

• Initial purchase price of sexually mature bulls or sows
• Larger aquarium and powerful filter setup costs
• Increased food budget to nourish adults weekly
• Calcium and water treatment supplements
• Potential vet bills for illness or injury care as they age

Plan for a moderate to high cost long-term commitment to properly supporting blue crayfish in adulthood. Budget $150-300 annually per mature pet on average.

Possible Behavioral Changes of a Fully Grown

Behaviorally, blue crayfish demonstrate the following shifts reaching sexual maturity:

• More aggressive territorial behavior from bulls
• Chasing and grappling as bulls compete for mates
• Maternal guarding of eggs by pregnant/berried sows
• Asserting dominance hierarchies within the aquarium
• Increased reactivity to perceived threats or intruders

Remain cautious of triggers that may spark confrontations between adult males in particular.

Notable Characteristics of a Fully Grown

Some distinguishing features that set full grown blue crayfish apart include:

• Larger size and bulkier claws/body
• Deeper, richer cobalt blue carapace color
• Well-defined secondary sex characteristics
• Mature reproductive behaviors and instincts
• Established personalities and temperaments
• Peak physical and muscle development
• Primed for reproducing as sexually mature adults

Their transformation into striking, formidable crustaceans at full size is quite evident.

Conclusion

With diligent care adapted to their maturing needs, blue crayfish can thrive for many rewarding years as pampered pets. Understanding the requirements of fully grown individuals sets fanciers up for success in maintaining blue crayfish healthily through adulthood.