Geographic Setting. The Colorado River Basin (CRB) is home to 22 fish genera, at least 35 fish species and at least 26 endemic fish species, some of which have persisted for over 10 million years (Evermann and Xxxxxx 1895, Xxxxxx 1959, Xxxxxx 1980, Xxxxxxxx et al. 1986, Xxxxxxx and Xxxx 1989, Xxxxxx and Xxxxxxxxx 1998, Xxxxxxxxxx and Xxxxxxx 2002). Geologic isolation, frequent drought and flood, widely ranging temperatures, and high sediment and solute loads in the CRB created a harsh environment that provided a unique setting for the evolution of a distinct group of endemic fishes (Xxxxxx 1980, Ono et al. 1983, Minckley et al. 1986). The CRB is divided into upper and lower basins at Xxx’x Ferry in north central Arizona, near the Utah border. The San Xxxx, Colorado, and Green river basins form the upper CRB. In the lower CRB, the Colorado River flows through Grand Canyon National Park and forms state boundaries between Nevada, California and Arizona. Conjoining the Colorado River in Arizona are the Little Colorado and Xxxx xxxxxx and the Virgin River joins the Colorado in Nevada. The three species occur in both upper and lower portions of the CRB. The Bonneville Basin (Utah, Nevada, Wyoming, and Idaho) is an endorheic basin, wherein surface water collects from precipitation and upwelling groundwater, but no streams drain out of the basin (Xxxxx et al. 1974). Historically, the Bonneville Basin had aquatic affinities with Xxxxxx Bay, and several species stem from northeastern North American progenitors (Xxxxxx and Xxxxxx 1996 and references therein). During geologic history, the Bear River flowed into the Upper Snake River drainage (Columbia River Basin), but currently flows into the Bonneville Basin (Xxxxx and Xxxxxx 1948; Xxxxxx and Xxxxxx 1996). The bluehead sucker historically occurred in both the CRB and the Bonneville Basin. Species Descriptions, Life Histories and Hybrids The three species share several morphological similarities commonly associated with hydrologically variable environments, including: 1) fusiform bodies, 2) leathery skins with embedded scales, and 3) large, often falcate fins. Such morphologic features, combined with relatively long life spans, may be adaptations to the harsh, unpredictable physical environment of the CRB (Scoppettone 1988, Minckley 1991, Xxxxxxx 1993, Xxxxxxxxxx and Xxxxxxx 2002). Life history characteristics, distribution and abundance have been described for roundtail chub (Xxxxxxx and Xxxxxx 1989, Xxxxxxx et al. 2000, Xxxxxx 2002), ...
Geographic Setting. The San Diego Regional Harbor Monitoring Program (RHMP) addresses four harbors in southern Orange and San Diego Counties. These include Xxxx Point Harbor, Oceanside Harbor, Mission Bay and San Diego Bay (Figure 2). Xxxx Point Harbor is located in the City of Xxxx Point in southern Orange County. It has berths for up to 2500 pleasure craft in two separate marinas. The harbor is protected by a single jetty that parallels the coast. There are no significant freshwater inputs to Xxxx Point Harbor other than storm drains servicing the local area. A variety of land uses occur around the harbor, including commercial (retail and restaurants), marina-related industry (fueling and dry-dock) and recreation. Oceanside Harbor is located in the City of Oceanside in northern San Diego County. The Oceanside Harbor has berths for 950 pleasure craft and additional anchorage for U.S. Coast Guard vessels, commercial and sport fishing vessels. There are no significant freshwater inputs to Oceanside Harbor other than storm drains servicing the local area. Retail shops and restaurants are located on the piers around the harbor and there is one fuel station. There are also residential units and recreational opportunities adjacent to the harbor. Separated from Oceanside Harbor, but protected by the same jetties, another harbor approximately ¼ mile north supports U.S. Navy vessels operating at Camp Xxxxxxxxx. Mission Bay is located in the City of San Diego in central San Diego County. Mission Bay is one of the largest man-made recreation aquatic parks in the world, encompassing 4,235 acres that used to be predominantly marshland until the mid- twentieth century. Tecolote and Xxxx Xxxxxx discharge into the eastern side of the Bay. Storm drains and groundwater discharge enter the Bay. There are numerous marinas and anchorages in Mission Bay, located primarily in the southwest corner, near the entrance to the Bay. Xxxxx beaches surround most of the bay, with the majority of adjacent land uses parks and residential areas. Mission Bay and the surrounding parks are used year-round for walking, jogging, picnicking, and a variety of water contact sports, including swimming, sailing, water-skiing and fishing. San Diego Bay is located in the City of San Diego. The entrance to San Diego Bay is between Point Loma on the west and North Island to the east. The bay curves around North Island and extends to the south, bound by the Silver Strand on the west and the Cities of San Diego, National Cit...
