Local management found helping some kelp forests thrive

A global analysis indicates that while global factors associated with climate change are generally harming kelp, some kelp forests are staying stable or even increasing, doing surprisingly well in many places.

The study, the first of the kind, led by Fiorenza Micheli, a professor of marine science at Stanford University, does recognizes the fact that a greater percentage of kelp forests, the green ecosystems that provide services such as fish feeding grounds and coastal storm protection, are declining due to negative effects of climate change.

However, Micheli and her colleagues have identified that there are large regional differences in the drivers of local environmental change and local management can play a major role in species survival by easing damage from impacts such as fishing, pollution and coastal development, leading to their findings that kelp in 27 percent of the regions analyzed show increases, 35 percent show no net change and 38 percent show declines.

"There is a sense that local efforts to protect and recover ecosystems are futile in the face of global environmental change," Micheli talked about the study published on Monday in Proceedings of the National Academy of Sciences. "Our findings show that local drivers of kelp forest decline can combine with and exacerbate the effects of global drivers, or even outweigh them in some cases. So, local management can be effective in maintaining or recovering these diverse and valuable ecosystems."

Based on data showing trends of kelp abundances from 1,138 sites monitored over the past half-century, regions in which the researchers documented kelp declines were often those experiencing multiple local stressors such as fishing and global stressors such as climate change; and regions where they found increases were often those with stories of successful local management.

The researchers point out a "noticeable lack" of baseline data in many regions against which to measure change. "It is becoming increasingly difficult to maintain monitoring of the coastal marine environment, but it is more important than ever that we keep the pulse of marine ecosystems in the face of mounting global and local stress," Micheli was quoted as saying in a news release from Stanford.

In part because of the unique capacity of kelp to recover quickly from disturbances, it is a different story from that of many other species, such as corals and seagrasses, which have seen global declines. Endit