Sockeye salmon swimming over dead salmon at spawning ground


Semelparous organisms reproduce only once in their lives and then die. The most well known ones are Pacific salmon that perish after spawning. Other examples are squid, mayflies and plants which die after setting seed (annuals). The adult diverts resources into producing huge amounts of offspring to ensure sufficient numbers reach maturity without any parental care. This is why bears largely ignore dead salmon after they've spawned - all the salmon's fat has gone into producing sperm and eggs and little nutrional value is left.

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BBC News about Semelparous

  • Chameleons live fast, die young The short but spectacular life cycle of the Labord's chameleon, the shortest-lived land vertebrate in the world, is filmed by BBC documentary makers.

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