Fishes. Two of the occupied sites in the historical range of the relict leopard frog are dominated by a variety of introduced nonnative fish species, including mosquito fish (Gambusia affinis), tilapia (Tilapia mossambica), a suite of tropical aquarium fishes such as cichlids (Cichlasoma spp.) and mollies (Poecilia spp.). Areas of the Muddy and Virgin rivers within the historic range of the relict leopard frog are dominated by introduced, invasive fish species including blue tilapia (Tilapia xxxxx), red xxxxxx (Cyprinella lutrensis) and mollies. Large, perennial aquatic habitats in the current range of the relict leopard frog are dominated by sportfish including members of the Centrarchidae (bass, sunfish), Ictaluridae (catfish), and Salmonidae (trout) (Xxxxxx et al. 1964, Xxxxxx et al. 1999, Xxxxxxxx 1973, NDOW unpublished data, NPS unpublished data). Many of these nonnative fishes represent a threat to relict leopard frogs, particularly for early life stages, through competition and direct predation. Although specific threats from some of the smaller aquarium fish species are not fully understood, predation on anuran larvae by Gambusia spp. has been well documented (XxXxxxxxx and Xxxxx 2000). Dietary studies of closely related Tilapia species in headwater spring outflows of the adjacent Muddy River system have shown them to be aggressive, opportunistic predators on a variety of aquatic species (X. Xxxxxxxxxxx pers. comm.). Trout prey on native fish and amphibians and have been linked to declines of amphibians in the western US, especially in historically fishless waters (Xxxxxxxx et al. 1993, Xxxxx and Xxxxxxxx 1986, Xxxxx and Xxxxxxxx 2000, Xxxxxxx and Xxxxxxxx 2001, Xxxxxxxx et al. 2000). These nonnative fish also compete with native fish and likely do so with amphibian larvae (Xxxxxx and Matter 1996, Xxxxx 1991). While trout do occur in the Colorado River reservoirs and headwater areas of the Virgin River basin, the ecological impact of these predators on the relict leopard frog is not well documented. No areas where stocked salmonids and the relict leopard frog co-occur have been documented Bullfrogs Bullfrogs have been introduced throughout western North America (Xxxxxx and Xxxxxxx 1991, Xxxxxx and Xxxxxx 1949). Bullfrogs are widely distributed within the current and historical range of the relict leopard frog and have been documented in occupied habitats at Littlefield, Arizona, and at historical sites where the leopard frog has been extirpated (AGFD unpub...
Fishes. Loaves Vocational and Literacy Center does not guarantee the transferability of credits to another school, college, or university. Credits or coursework are not likely to transfer; any decision on the comparability, appropriateness and applicability of credit and whether credit should be accepted is the decision of the receiving institution.
Fishes. There is no fish habitat in or near the Project Area. The nearest perennial stream channel is the Santa Xxxxx River, four miles to the south. Birds The Reserve and Snow Canyon State Park provide habitat for many bird species. Canyon xxxx (Catherpes mexicanus), scrub xxx (Aphelocoma californica), various sparrows (Amphispiza sp.), and Xxxxxx’x quail (Callipepla gambelii) were observed during field surveys. Birds of conservation concern listed by the USFWS and/or Partners in Flight (PIF) that may occur in the Project Area are listed in Table 4 and are described below. Table 4. Birds of conservation concern occurring in the Reserve that may occur in the Project Area. COMMON NAME SCIENTIFIC NAME LIST Golden eagle Aquila chrysaetos BCC Northern harrier Circus cyaneus BCC Peregrine falcon Falco sparverius BCC Xxxxxx’x quail Callipepla gambelii PIF Loggerhead shrike Xxxxxx ludovicianus BCC Sage sparrow Amphispiza belli BCC, PIF BCC = Birds of Conservation Concern (USFWS), PIF = Partners in Flight (Priority Species). City of Xxxxx Detention Basin Project 26 Environmental Assessment Golden eagle: Golden eagles occur in open country within tundra, shrublands, grasslands, woodland-brushlands, open coniferous forests, and occasionally riparian habitats. These eagles prefer to breed in elevated nest sites that are isolated from human activity, usually sheltered ledges on cliff faces near hunting areas. They will nest in trees and occasionally on the ground in the absence of suitable cliffs. Golden eagles are year-round residents in southern Utah (Hawkwatch 2005) and may use the Project Area for foraging and the cliffs within Padre Canyon provide nesting habitat, although no individuals or nests were observed during surveys in March 2005. Northern harrier: Northern harriers are found most often in marshes, xxxxxxx, and fields. Most individuals remain in Utah year-round, hunting for small rodents and birds. Nests consist of sticks and grasses, and occur on the ground or on low vegetation. The Project Area does not provide typical habitat for this species. Peregrine falcon: Peregrine falcons nests on tall cliffs near, and often directly above streams, rivers, or reservoirs. Nests are shallow scrapes placed in cracks, holes, and small caves on cliff faces. Typical prey include waterfowl, shorebirds, doves, swallows, swifts, and meadowlarks. Although some individuals leave Utah for the winter, many reside year-round. Breeding and nesting typically begin in late March or ear...
Fishes. The fish species that occur in Fram Strait are a mixture of boreal and Arctic demersal and pelagic species. Boreal fishes such as Atlantic cod, xxxxxxx, and blue xxxxxxx extend their range into Fram Strait with the flow of the WSC. Boreal species’ ranges overlap with arctic fish species, such as polar cod. The majority of fish species in Fram Strait are small, benthic Arctic species, with the exceptions of the Greenland shark and Greenland halibut (Hop et al. 2006). The Greenland shark (Somniosus microcephalus) also known as the “sleeper shark,” is the largest member of the dogfish family and can grow to over 6.4 m in length and weigh up to 907 kg. Primarily, this shark species inhabits the deep waters around Greenland and Iceland to depths of 2,000 m. No other shark resides at the high northern latitudes that the Greenland shark is found. One fish species that potentially occurs in the ACOBAR Experiment area is the Atlantic cod, which is listed under IUCN’s vulnerable category. No fish habitat is specifically protected under Norwegian or IUCN regulations in the Fram Strait area. ] Atlantic Cod (Gadus morhua) Atlantic cod are listed as vulnerable under the IUCN (Xxxxx 1996). Atlantic cod are demersal cold- temperate fish that are distributed in the North Atlantic Ocean waters from Greenland to the southeastern United States (Xxxxxxxx 2007). Oceanic populations of Atlantic cod are highly migratory and travel thousands of kilometers to spawn in generally the same areas each year (Xxxxxxxxx et al. 2008). The northeastern Arctic cod stock migrates from oceanic feeding grounds to spawning areas in coastal waters annually (Xxxxxxxxx et al. 2008). The Atlantic cod populations during the 18th and 19th centuries were severely over-fished and fishing in some regions of the North Atlantic was closed to cod harvest (Fu and Fanning 2004). Atlantic cod are still a main fishery today for various northern Atlantic coastal countries.
Fishes. Fish can be classified by their hearing capabilities. A number of fish, found in widely diverse groups, have physiological adaptations that enhance their hearing capabilities. These fish, often called “hearing specialists,” can hear a wider range of sound frequencies and sounds of lower intensities than fishes that are “hearing generalists” and do not possess the adaptations (Xxxxxx and Xxx 1993). The upper frequency limit for hearing generalists varies by fish species. The upper frequency for a hearing generalist may be as low as 200 Hz in a flatfish or perch and as high as 800 Hz in some salmon, but best hearing is generally in the center of the hearing range. Hearing specialists hear a wider range of hearing frequencies, with the upper range most often reaching 2,500 to 4,000 Hz. Best sensitivity in hearing specialists generally ranges from 200 to 800 Hz. Hearing ability in fish is also affected by the duration of the sound stimulus. As the stimulus begins to decrease in duration, the hearing threshold (generally defined as the minimum sound level detectable at a particular frequency) begins to increase. In other words, as a signal gets shorter, it is harder for fish to detect. The potential effects of high-intensity underwater sounds on fishes may include TTS, increased stress levels (Xxxxx et al. 2004a, b), and/or damage to other organ systems such as the circulatory system and the swim bladder (Hastings and Popper 2005). There is also the potential for behavioral effects, including movement away from the source and alterations in feeding and mating (Slotte et al. 2004). Recent research on rainbow trout (a hearing generalist closely related to salmon) exposed to high-intensity (RL of 193 dB re 1 µPa rms), low-frequency (170 to 320 Hz) signals of 324 or 648 sec duration found no effect on non-auditory tissues and no indication of damage to sensory hearing cells (Xxxxxx et al. 2007). However Xxxxxx et al. (2007) did find that some trout experienced 20 to 25 dB of TTS at 400 Hz up to 48 hr post-exposure. Xxxxx et al. (2004a, b) found that goldfish, a hearing specialist, experienced 5 dB of TTS after 10 min of exposure to 0.1 to 10 kHz band-limited noise at approximately 170 dB RL overall spectral sound pressure level. In contrast, tilapia, a hearing generalist, showed no TTS after up to 21 days of similar exposure at 170 dB. Data on shark hearing are very limited and in need of replication and expansion to include more species and more specimens. Some re...
