Day: November 17, 2017

One major aspect of changing human behavior to minimize and mitigate disturbance is through education and awareness. In the case of invasive species, informing people about the consequences of transporting plants and animals to new places will mitigate the spread of invasive species. For fire disturbance, educating people on the dangers of fire suppression as well as how fires benefit an ecosystem may influence greater acceptance and better management. Grazing can be better managed by the knowledge and use of Grazing Systems. Governmental policy is also effective in changing societal behavior, for example a carbon tax can minimize the human impact on climate change by limiting emissions. In order to change individual human worldviews, educated discussion and supported facts go a long way to convince people to consider ideas that they haven’t before.

The Human Footprint is an important factor influencing management methods. Disturbance is greatly impacted by human urbanization, and can be better managed if we understand the relationship between human activity and the effects of disturbance on different ecosystems. Research on the Human Footprint helps to minimize and mitigate disturbance, and has developed as “humans have dramatically altered wildlands in the western United States over the past 100 years by using these lands and the resources they provide. Anthropogenic changes to the landscape, such as urban expansion and development of rural areas, influence the number and kinds of plants and wildlife that remain. In addition, western ecosystems are also affected by roads, powerlines, and other networks and land uses necessary to maintain human populations. The cumulative impacts of human presence and actions on a landscape are called the “human footprint.” These impacts may affect plants and wildlife by increasing the number of synanthropic (species that benefit from human activities) bird and mammal predators and facilitating their movements through the landscape or by creating unsuitable habitats. These actions can impact plants and wildlife to such an extent that the persistence of populations or entire species is questionable…The human footprint aids managers in planning, implementing land-use actions, and developing strategies to conserve habitats and wildlife. Modeling the human footprint across large landscapes also allows researchers to generate hypotheses about ecosystem change and to conduct studies in regions differing in potential impact. Because funding for restoration and conservation projects is limited, and because there is little room for errors in the management of species of concern, land managers are able to maximize restoration and conservation efforts in areas minimally influenced by the human footprint. As such, the human footprint model is an important first step toward understanding the synergistic effects acting on shrublands in the western United States.” (USGS). The Human Footprint measures the negative or positive changes that humans have made to a landscape. It includes factors of urbanization, recreation, Energy development, and climate change. All of these things are valuable or inevitable, but educated management can help make these things sustainable. Considering the areas least impacted by the human footprint allows managers to consider what ecosystem is worth the time, money, and effort to repair and research.

https://pubs.usgs.gov/fs/2003/0127/fs12703.pdf

USGS. The Human Footprint in the West: A Large-scale Analysis of Human Impacts. US Department of the Interior. December 2003.

Lichatowich, Jim. Salmon without Rivers: a History of the Pacific Salmon Crisis. Island Press, 1999.

In Chapter 7 of Salmon Without Rivers, Lichatowich discusses solutions to the four main problems causing the declining abundance of salmon: facilitating salmon egg transfer, eliminating predators of salmon, controlling ocean troll fishery, and strengthening salmon passage at high dams (pg 152). In 1925, experts met in Seattle; finally acknowledging and discussing the extent of these issues, and how to solve them. One conclusion that came from the meeting was that substantial research of salmon and their decline was still needed (proposed by Gilbert). Considered by some to be the first fisheries biologist in the US, “as early as 1913, Gilbert had used an ingenious method to work out the basic life histories of the Pacific Salmon…The salmons scales grow roughly in proportion to the growth of the fish, and as the scales grow, circular ridges are deposited on their surface. These rings, called circuli, are similar to the rings in a cross sectional cut of a tree. Narrow spacing between tree rings means slow growth, whereas wide spacing indicates rapid growth” (pg 164). This methodology still influences current knowledge of salmon life history, for example, from Gilbert’s idea of dividing “juvenile salmon into two general categories, stream and ocean, based on their life histories. Stream-type fish remained in fresh water for a year and migrated to sea in the spring of their second year of life. Ocean-type fish migrated to sea shortly after emerging from the gravel during their first year of life” (pg 164). As you can see, Gilbert’s findings about scales provided information that led to a topic integral to fish conservation: life history. This advancement in the knowledge of Pacific salmon life history improved harvest recommendations by expanding our understanding of issues like the homing of salmon, and when hatcheries should release them. Life history answers broad questions like, what/ when/ where/ and how salmon do things; and also very specific questions like, “that salmon populations were composed of individual fish that exploited their environment in different ways. He speculated that this life history diversity had an ecological basis, and that it was an integral part of the relationship between the fish and it’s environment” (pg 165). One issue that hatcheries (at the time) had with Gilbert’s findings was that they believed that human controlled production was more efficient than natural ecological processes (165), and therefore continued to degrade fish natural life history by operating hatcheries on their own terms. By taking a more ecological and scientific approach, harvest management can be improved. All of the problems causing the decline of salmon, introduced in the 1920’s Seattle meeting, are human caused. Researching salmon life history, and applying convergent evidence to harvest management, will likely improve salmon abundance.

Other aspects of salmon ecology that should be considered are the general changing effects that human urbanization has on salmon habitat. Examples include the effects of climate change, recreation, disturbance, and energy development. By studying and managing these things with a greater environmental ethic, humans can create greater biodiversity of salmon habitat, and provide better chances for natural ecological processes to work.

https://www.nationalgeographic.com/animals/mammals/n/nutria/

An invasive species that I have seen in my hometown of Newberg Oregon is Nutria (Myocastor Coypus). They inhabited the forest/creek that ran through my families backyard and around our Cul-de-sac. Nutria compete with native species for food, resources, and habitat. They also cause destruction to natural landscape through burrowing.

“Nutria are native to South America and were introduced deliberately into North America for fur farming in the 1930s. In Oregon, the species is limited to areas in the southern Willamette Valley and central Coastal Region. It usually occurs in or adjacent to rivers, lakes, sloughs, marshes, ponds, and temporarily flooded fields. Nutrias construct burrows in banks of rivers, sloughs, and ponds, sometimes causing considerable erosion.” (https://myodfw.com/wildlife-viewing/species/invasive-species (Links to an external site.))

This invasion could have been prevented in multiple ways. Their transportation from South America, simply for economic benefit through fur farming, could have been prevented. Establishing hundreds of Nutria Farms in the Pacific Northwest could have been prevented. Farmers releasing Nutria when it became uneconomical, also could have been prevented. This invasion could have been prevented if the economical benefits of fur trade didn’t influence people to transport them here and establish farms.