Unusual Marine Life in the Baltic Sea: Ghost Crabs, Sea Hares, and Pikes - Unique Baltic Sea Marine Life: A Fascinating Discovery
The Baltic Sea, a unique marine ecosystem, is facing significant challenges due to climate change and human activities. This vast body of water, which resembles a dragon with its jaws wide open from above, is home to a large number of remarkable animals, many of which have adapted to its cold, brackish environment.
As one travels east and north in the Baltic Sea, the salinity decreases due to the influx of fresh water from rivers. However, in the northeast of the Baltic Sea, the water is very salty and biologically similar to the North Sea. This varying salinity is a factor in the diversity of its animal life, contributing to its distinctive biological makeup.
Some unique species in the Baltic Sea include the Saimaa ringed seal, a glacial relict, and the microscopic phytoplankton Skeletonema marinoi. The Saimaa ringed seal is a cold-adapted species, with specialized tooth adaptations that distinguish it from other ringed seals, feeding mainly on fish and suction-filter feeding on small marine invertebrates. It is genetically unique, possibly a distinct species, and highly vulnerable to extinction due to its limited distribution and lack of related populations to replenish it.
Skeletonema marinoi, on the other hand, can enter a dormant state in Baltic Sea sediments and has been revived after being dormant for nearly 7,000 years, demonstrating extraordinary resilience and adaptation to past climate conditions. This ability to survive long sediment burial enables it to serve as a biological “time capsule,” helping scientists study ecological history and adaptations to environmental changes over millennia.
However, these and other Baltic Sea organisms are currently affected by ongoing climate change and human impacts. The Eastern Baltic cod, for example, is experiencing human-driven evolutionary changes due to overfishing, with genetic shifts favoring smaller, faster-maturing fish—a response to selective harvest of larger individuals. Moreover, this cod population faces stresses from warming temperatures, diseases, parasites, and declining salinity caused by increased freshwater inflow. The Baltic Sea has recently recorded some of its warmest water temperatures, which alongside other stressors, threaten the survival of adapted species.
The Baltic Sea's climate change is also impacting fish species that require low temperatures for spawning. Many of these species are increasingly disappearing from the Baltic Sea. In contrast, jellyfish, which tolerate higher temperatures, are increasingly penetrating into the Baltic Sea. The rising water temperatures in the Baltic Sea, similar to a large bathtub, are causing this shift, contributing to the increase in jellyfish population.
Jellyfish in the Baltic Sea are making life harder for humans. Their blooms can clog fishing nets, disrupt fisheries, and even pose a threat to beachgoers. The Baltic Sea, once a vibrant and diverse ecosystem, is struggling to maintain its balance under the pressures of climate change and human activities. It is crucial that we understand and address these challenges to ensure the survival of this unique marine environment and the species that call it home.
- Adopting a home-and-garden lifestyle that includes suitable plants could help promote biodiversity and support the Saimaa ringed seal, a unique species found in the Baltic Sea, as part of its habitat conservation.
- In the home-garden setting, one might consider planting native species that provide food for the Skeletonema marinoi, a resilient phytoplankton found in the Baltic Sea sediments, as a small contribution to the overall health of the Baltic Sea ecosystem.
