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One example of wildlife-related linkages is that amphibians occupy both aquatic and terrestrial habitats. They play an integral role in the ecology and nutrient cycling both on land and in the water. Scientists have concluded that maintaining and restoring hardwood forest canopies is crucial to the persistence of amphibians around the Gulf of Maine. Since they migrate and use different areas during certain life stages, spotted salamanders, wood frogs, and wood turtles require a certain amount of forest area and connectivity of intact forest habitat. Conversely, from an aquatic perspective, some species such as spring salamanders live in small, ephemeral streams, which may not support fish, making protection of these headwater streams critical. For amphibians, the most responsible management strategy, according to some scientists, is to mimic the frequency and size of natural disturbances to the habitat. Other animals require both aquatic and terrestrial habitats for feeding, breeding or other activities. For example, some fish spawn in seasonally flooded riparian forests, and loss of forest habitat with the appropriate topography next to a stream may jeopardize their survival. Similarly, some insects spend part of their life cycle underwater, and the other part as airborne inhabitants of the forest. They are a component of the food webs in both the aquatic and terrestrial worlds. Anything that affects the population of these insects on land might have ripple effects into the aquatic ecosystem and vice versa. Its another reason why the notion of separate aquatic and terrestrial systems may be largely illusory. Some species blur the aquatic-terrestrial boundary in ways that are more subtle but no less significant. For example, mammals like mink, beaver and river otter play an important role in nutrient exchange by foraging in aquatic habitats and defecating in terrestrial areas. This transfer of nutrients from water to land may be important in providing fertilizer for some forest plants. The interchange continues when forest plants next to water bodies drop their leaves and twigs, providing a vital source of organic matter for the aquatic food web. Some of the matter falls directly into the water, while other bits may fall to the ground and be transported by rain or snowmelt. In recognition of this process, managers ought to consider that reductions in forest canopy may influence the stream-dwelling invertebrate community because of loss of energy entering the streamwhich could in turn affect other fish and wildlife resources. The protection of shoreland buffers can even benefit wildlife species that ordinarily do not need riparian habitat. In some places, shoreland buffers offer the only intact forest habitat in an otherwise heavily developed, farmed, or logged landscape. Consequently, the buffers act as vital travel corridors and refuges for creatures that could thrive far from the waters edge, if only the habitat hadnt been destroyed. While scientists are still exploring the relationships among wildlife and riparian habitats around the Gulf of Maine, it is not too soon for some basic principles to be incorporated into shoreland regulations and management plans to help wildlife persist. Some initiatives by towns, states, provinces, federal agencies and private landowners around the Gulf of Maine are using the recent regional findingsalong with information gleaned from elsewhereto improve management of riparian areas and sustain the role of wildlife in these important ecosystems. The Science Translation Project of the Gulf of Maine Council is developing information resources to facilitate such efforts. Peter Taylor (ptgomc@suscom-maine.net) is a science translator for the Gulf of Maine Council on the Marine Environment. For information about the Science Translation Project and its sponsors, visit www.gulfofmaine.org/science_translation.. © 2004 The Gulf of Maine Times |