Starfish, admired for their unique shapes and vibrant colors, captivate many who encounter them along coastlines. Many wonder: does picking up a starfish cause it harm? Understanding the delicate biology of these marine creatures reveals that, despite good intentions, handling them can have detrimental effects. Appreciating marine life prioritizes their well-being and ecosystem health.
How Starfish Are Built
Starfish, also known as sea stars, possess a body structure distinct from vertebrates, lacking a rigid skeletal system. Instead, their internal support comes from an endoskeleton made of numerous small, calcified plates called ossicles, embedded within their skin. These ossicles are connected by flexible tissues, allowing for some movement despite their seemingly rigid form.
A defining feature of starfish is their water vascular system, a hydraulic network that extends throughout their body and into their arms. This system plays a role in various functions, including locomotion, feeding, gas exchange, and waste transport. Seawater enters this system through a sieve-like plate on their upper surface called the madreporite and circulates through canals to their tube feet.
Tube feet, or podia, are tubular projections located on the underside of each arm. These delicate structures operate through hydraulic pressure from the water vascular system, enabling the starfish to move, cling to surfaces, and manipulate food. Starfish also breathe using thin-walled projections called dermal branchiae, or skin gills, which facilitate the exchange of oxygen and carbon dioxide.
The Risks of Handling
Picking up a starfish can damage its anatomy. Their numerous tube feet, important for movement, feeding, and gripping, can be dislodged or ruptured when handled. This damage impairs the starfish’s ability to navigate its environment and obtain food, potentially leading to starvation.
Exposure to air poses a threat to starfish. When removed from water, their dermal branchiae collapse, reducing oxygen absorption. A few minutes out of water can be detrimental; most starfish can only tolerate being out of water for 3 to 5 minutes before experiencing distress or death.
Removing a starfish from water also disrupts its internal pressure. Starfish depend on water’s buoyancy to support their internal organs; out of water, these organs experience stress. Human hands can carry oils, lotions, sunscreens, or bacteria toxic to starfish. The physiological stress from handling can also weaken a starfish’s immune system, making it more vulnerable to disease after release.
Responsible Starfish Encounters
The most responsible approach when encountering starfish is to observe them without physical contact. Allowing marine animals to remain undisturbed in their natural habitat helps ensure their continued health and survival. If a starfish is found on the shore, it is best to leave it unless it appears to be in immediate distress and needs to be gently returned to the water, supporting its entire body with wet hands.
When exploring tide pools, walk gently and watch your footing to avoid disturbing marine life. Resisting the urge to touch or pick up starfish, even briefly, minimizes stress and prevents injury or contamination. This hands-off policy extends to all marine creatures.
Educating others about the vulnerabilities of starfish and the importance of responsible viewing practices helps foster a culture of conservation. If you encounter an injured or stranded marine animal, contacting local marine animal rescue networks or authorities is the appropriate action, allowing trained professionals to provide assistance.