Climate change impacts on potential recruitment in an ecosystem engineer

Area of Science:

• Marine Biology
• Ecology
• Reproductive Biology

Background:

• The common cockle (Cerastoderma edule) is a vital ecosystem engineer in coastal habitats.
• It plays a crucial role in nutrient cycling, sediment structure, and marine food webs.
• Coastal ecosystems face challenges from climate variability and changing sea conditions.

Purpose of the Study:

• To investigate the effects of climate variability on gametogenesis and spawning in Cerastoderma edule.
• To compare reproductive timing between two Special Areas of Conservation (SACs) with differing water quality.
• To determine the dominant factors controlling reproductive processes in this key species.

Main Methods:

• Field study conducted at two distinct sites on Ireland's south coast (early 2010-mid 2011).
• Monitoring of gametogenesis and spawning periods in Cerastoderma edule populations.
• Analysis of environmental data, including water quality and temperature, in relation to climatic conditions.

Main Results:

• Slight variations in spawning periods were observed between the two sites, despite differences in water quality.
• Temperature and variable climatic conditions were identified as the primary drivers of gametogenesis.
• The spawning period was found to be longer than previously reported, with gametogenesis initiating in winter.

Conclusions:

• Extreme cold winters may accelerate and extend the onset and development of gametogenesis in Cerastoderma edule.
• The success of this extended gametogenesis into recruitment depends on the availability of primary producers and spring blooms.
• Climate variability, particularly winter temperatures, significantly impacts the reproductive cycle of this important marine bivalve.