Pacific Lamprey: The Ancient Bloodsucker

Pacific Lampray showing the part of its body that sucks blood from marine mammals
Pacific Lampray. Image credit: USFWS Fish and Aquatic Conservation via flickr, Public Domain
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Here is another Halloween-worthy creature: The Pacific lamprey is a fascinating eel-like animal, a jawless, boneless parasite that’s been around for over 450 million years. It’s also one of the most successful parasites on Earth, having survived at least four mass extinction events. They are boneless marine animals with a cartilaginous skeleton and grow to about 80 cm (31 in) as adults.

Approximately 40 lamprey species trace their lineage back to a common jawless-fish ancestor that emerged during the Ordovician period (began 485.4 million years ago, following the Cambrian Period, and ended 443.8 million years ago). As a collective, they have demonstrated remarkable resilience, withstanding a minimum of four major extinction events throughout their evolutionary history.

Pacific lampreys (Entosphenus tridentatus) start their lives in freshwater rivers and streams. After a few years, they migrate to the ocean, where they spend most of their adult lives. When they’re ready to spawn, they return to freshwater to lay their eggs.

Pacific lampreys are bloodsuckers. They use their spherical, jawless mouths to attach themselves to fish and marine mammals and drink their blood. They don’t usually kill their hosts, but they can leave nasty wounds.

Pacific lampreys play an important role in their ecosystems. They’re a food source for birds, mammals, and other fish and also help to control populations of other fish species.

Here are some interesting facts about the Pacific lamprey:

  • They have a third eye on top of their head. This is a specialized light-sensing organ.
  • They can detect chemical cues released by other lampreys. This helps them to find their way back to freshwater to spawn.
  • They can transform from a marine animal to a freshwater animal. This is a remarkable feat, and it requires a number of changes to their physiology.
  • They have a particularly nasty feeding strategy. They use their spherical, jawless mouths to attach themselves to fish and marine mammals and drink their blood.
  • They are an important food source for other animals in their ecosystem.
  • They have survived at least four mass extinction events. This is a testament to their resilience.

The Pacific lamprey is a truly unique and fascinating creature. It’s a living fossil that has survived for over 450 million years, far longer than the dinosaurs and older than trees. It’s also a boneless and jawless bloodsucker that plays an important role in its ecosystem.

The Pacific lamprey is a truly Halloween-worthy creature. It’s a reminder that there are still strange and wonderful creatures out there in the world. Unfortunately, Pacific lamprey populations have seen a significant decline as a result of human-made infrastructure. The construction of dams, river channelization, and deteriorating water quality have all taken a toll on Pacific lamprey habitats and their survival prospects.

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I am a Chartered Environmentalist from the Royal Society for the Environment, UK and co-owner of DoLocal Digital Marketing Agency Ltd, with a Master of Environmental Management from Yale University, an MBA in Finance, and a Bachelor of Science in Physics and Mathematics. I am passionate about science, history and environment and love to create content on these topics.

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