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At least 523 records · Page 29Linked to original sources
USGS1996

Similarities and life cycle distributions of floras of 22 national parks in the midwestern United States

Twenty-two midwestern U.S. national parks were studied to examine the similarities of their floras and analyses of the floras in each national park were used to construct groupings of these smaller sample areas at various similarity levels in order to classify larger floristic areas. The parks were not on average very similar based on Jaccard's similarity index. The maximum average park similarity was 21% (St. Croix National Scenic Riverway), and the maximum park pair similarity was just over 55% for Isle Royale National Park and Pictured Rocks National Lakeshore. The average similarity of parks increased with park area and numbers of native species, and weakly decreased with the percentage of non-native species. Weak trends were observed with latitude and negative trends with longitude. Four park groups were partitioned by cluster analysis of species relative abundance data: 7 prairie parks, 6 northern parks, 4 intermediate parks and 5 southern parks. The average percentage of non-native species was ~33% in the prairie and southern park clusters, while percentage of evergreen perennials was 2 to 4 times greater in the northern parks (8%) compared with other clusters. Deciduous perennials approached 80% in the northern and intermediate park clusters, compared with about 70% for the prairie and southern clusters. Percentage of annuals was almost double in the prairie and southern clusters (average 24%) compared with the northern and intermediate clusters (average 13%).

Illinois, Indiana, Iowa, Kansas, Michigan, Minneso↗
USGS2000

Thinking outside the lines: Parks and the quality of life in area communities

Many national parks, national forests, and other public land units exist in highly changeable regional environments. Often the parks and forests themselves serve as important catalysts of change in the levels of tourism, outdoor recreation participation, and contribution of traveling publics to local and regional economies. Resource managers are called upon to protect lands in their jurisdictions while juggling a variety of inputs and expectations. In each agency, resource decisions are bound by law and agency policy. In this context, the decision space of the national park manager is quite different from that of those in multiple-use land management agencies. Management actions must stand up, not only to law and policy and to scientific scrutiny, but they must also be sensitive to the needs of residents in surrounding communities, to county and state governing bodies, and to visitors from across the nation and around the world. Balancing these needs while protecting resources in an ongoing challenge made more difficult as the mix of stakeholders growsa?|

Park Science↗
USGS1993

Life history traits and habitat needs of the redhead

Redheads are one of five common diving duck species in North America. They are in the same taxonomic group as the pochards or bay ducks and are most similar in appearance and behavior to the canvasback. Smaller body size, late breeding, wintering in southern areas, and tolerance to salt in winter and in breeding areas differentiate the redhead from the canvasback and suggest an evolutionary origin in the arid areas of the West. Parasitism of other waterfowl nests is more pronounced in redheads than in other North American waterfowl. These and other aspects of the biology of the redhead are the subject of this leaflet. Readers who are interested in general references on redheads.

Fish and Wildlife Leaflet↗
USGS1974

Life history of the spottail shiner (Notropis hudsonius) in southeastern Lake Michigan, the Kalamazoo River, and western Lake Erie

In southeastern Lake Michigan spottail shiners in samples ranged from ages 0 to V, but most were in age groups I-IV. In the Kalamazoo River (a tributary of southeastern Lake Michigan) age group II was commonest in the catches, and no fish older than age IV were sampled. In western Lake Erie, most shiners were in age groups 0-II, and none were older than age IV. Mortality of males was much higher than that of females after age II in Lake Michigan and after age I in Lake Erie. Growth of spottail shiners was fastest in western Lake Erie (125 mm at the end of the third year, sexes combined) and slowest (77 mm) in the Kalamazoo River; in all three waters growth declined rapidly after the first year. Females grew faster than males. Young shiners started growing earlier in the year than older ones in all three waters. Males and females of the same age resumed growth at about the same time. The growing season began as early as mid-May in the Kalamazoo River and continued as late as September or early October in the other two waters. Small spottail shiners in Lake Michigan and the Kalamazoo River weighed about the same at a given length, but at lengths greater than about 100 mm the lake fish were heavier. In all three waters, spottail shiners matured at about the same length, and males at a somewhat smaller size than females. Smallest mature fish were 65-69 mm long, and the largest immatures were 80-84 mm. In Lake Michigan about half and in Lake Erie about three-quarters of age-I fish were mature, as were all age-II fish in both lakes. In the Kalamazoo River a few fish of age II and all of age III were mature. The spawning season in Lake Michigan in 1964 was from late June or early July to late July, whereas in 1972, which had a colder spring, spawning occurred from mid-July to late August or early September. All shiners in the Kalamazoo River had spawned by the end of June if 1964. Lake Erie spottail shiners spawned during early June to early or mid-July in 1958. Spottail shiners 87-143 mm long from the different waters contained 915 to 8,898 mature eggs.

Research Report↗