Declining Kelp Forests

In News

• According to experts, Global Kelp forests declining at 1.8% annually.

What are the Kelp Forests?

• Kelp forests are underwater areas with a high density of kelp, which covers a large part of the world’s coastlines. 
  • Smaller areas of anchored kelp are called kelp beds. 
• Kelp are not plants, but rather extremely large brown algae, and many different species of kelp make up kelp forests.

Features of Kelp Forests

• Kelp thrives in cold, nutrient-rich waters. 
  • Because kelp attaches to the seafloor and eventually grows to the water’s surface and relies on sunlight to generate food and energy, kelp forests are always coastal and require shallow, relatively clear water. 
• Growth:
  • Some kelp species can measure up to 150 feet (45 m) long. If living in ideal physical conditions, kelp can grow 18 inches (45 cm) a day.
• Habitat:
  • Kelps usually live further from the tropics than coral reefs, mangrove forests, and warm-water seagrass beds, so kelp forests do not overlap with those systems.
• Global presence:
  • Kelp forests grow predominantly along the Eastern Pacific Coast, from Alaska and Canada to the waters of Baja, California. 

Significance of the Kelp Forests

• They are recognized as one of the most productive and dynamic ecosystems on Earth.
• Kelps cover 25 percent of the world’s coastlines and provide food and shelter for fish, invertebrates and marine mammal species. 
• They also offer crucial services such as carbon sequestration and erosion control, according to scientists.
• Giant Kelp:
  •  Giant kelp is harvested from kelp forests and used as a binding agent in products like ice cream, cereal, ranch dressing, yogurt, toothpaste, lotion and more.

Threats to Kelp Forest

• Climate change and human-induced stressors:
  • Kelps are increasingly threatened by climate change, eutrophication and shoreline development, among other human-induced stressors. 
  • Destructive fishing practices, coastal pollution, and accidental damage caused by boat entanglement are known to negatively affect kelp forests.
• Warming of oceans:
  • Warmer than normal summers and seasonal changes to currents that bring fewer nutrients to kelp forests combine to weaken kelps and threaten their survival in some years. 
• Bryozoa:
  • One such threat is from bryozoa, moss animals that grow as mats on kelps. They drive the seaweed to sink into the seafloor and disintegrate.
    • The bryozoa outbreak can be linked to high temperatures as high temperature and kelp density results in more bryozoan.
    • Dense kelp beds in warmer and less wave-exposed sites are more susceptible to bryozoan outbreaks
• Storms: 
  • Strong individual storms can wipe out large areas of kelp forest, by ripping the kelp plants from the seafloor. 

Way ahead

• While it is unlikely that in situ protection could halt declines of rear edge kelp populations under scenarios of warming, their unique genetic diversity could be protected and studied ex situ in culture banks for use in restoration, hybridisation or assisted adaptation strategies

Source: DTE