Effects of Channelization on Fish Populations of the Cache River and Bayou DeView

This study was designed to better understand the possible effects of channelization by comparing natural and previously channelized sections of the Cache River and Bayou DeView. Forty-five fish species were collected in natural reaches, but only 24 species were collected in channelized reaches. Cyprinus carpio and Dorosoma cepedianum constituted 40 and 20 percent of the total fish biomass in channelized reaches, respectively, but only 22 and 2 percent of the total biomass in natural reaches. The mean weight of total fishes and game fishes only per surface ha in natural sections were 276 and 46 kg, respectively, but these values in channelized sections were only 88 and 2 kg, respectively. Mean species diversity indices for natural and channelized sections of the Cache River were 3.1 and 1.8, respectively, and mean redundancy values for these sections were .30 and .55, respectively. Species diversity indices and redundancy values for Bayou DeView followed this trend

Dragonflies of (Anisoptera) Arkansas

Previous publications have recorded 69 species of dragonflies for Arkansas. Three of these are deleted, but state records for 21 new species are reported herein, bringing the list to 87 species. Based on lists from adjacent states, an additional nine species are listed as probably occurring in Arkansas. County records are given for both naiads and adults of each species, as well as first and last capture dates for adults. Specific location and capture date are given for new state records when such data are available. The most species (39) have been reported from Washington County. Twenty-nine counties list from 1-5 species, and six counties list no records

Preimpoundment Ichthyofaunal Survey of the Piney Creek Watershed, Izard County, Arkansas

Piney Creek is a clear medium-size tributary of White River in a region of the Ozarks that is undergoing rapid environmental change. Piney Creek is characterized by a very diverse ichthyofauna, although increased sedimentation due to poor agricultural practices and gravel mining threatens to destroy much natural habitat and eventually may cause extirpation of some species. The wide diversity of 44 species is related to variety of habitat and the proximity of a large reservoir, and not to differences in the physicochemical environments. Fish density ranged from 15,100 to 21 fish/ha, greatest concentrations being in headwater pools. For the three most numerous cyprinids, mean weight per individual was greater in pools than in riffles. Okkelbergia aepyptera was collected for the second time in Arkansas (Harp and Matthews, in press), and a range extension for Notropis sabinae is reported

Limnology of Four Bauxite Open-Pit Lakes

The aquatic flora and fauna and 18 physicochemical characteristics of four bauxite open-pit lakes were studied from September 1969 to August 1970. The least acid lake (pH 3.4-4.4) supported 49 different aquatic insects, plankton, and higher aquatic plants. The most acid lake (pH 2.7-3.2) supported only 26 different plants and animals. Bauxite open-pit lakes within the pH range studied appear to be as relatively unproductive as their coal strip-mine lake counterparts, with which they share physicochemical and biological characteristics. Benthic macrofaunal diversity and abundance appear to be related more closely to distribution and abundance of leaf detritus than to hydrogen-ion concentration

Ichthyofaunal Diversification and Distribution in the Ozark Stream in Northcentral Arkansas

The distribution and diversity of the ichthyofauna of Arkansas are poorly known. This study is part of a continuing effort to elucidate the natural history of Arkansas. Big Creek is a relatively small, clear, cool-water stream in the Ozark Plateau of northcentral Arkansas. Big Creek and its tributaries drain into Lake Norfork, an impoundment on North Fork River. A total of 6,779 fish of 30 species was collected. Dominant pool species included Notropis boops, Fundulus catenatus, F. olivaceus, Labidesthes sicculus, and Campostoma anomalum; dominant riffle species included Etheostoma spectabile, E. caeruleum, Notropis boops, Fundulus catenatus, and Campostoma anomalum. The numerical standing crop ranged from 1.3 to 2.6 fish/m 2 in the pools and riffles, respectively. The relative uniformity of substrate and soil types throughout the watershed, and the absence of rooted aquatic plants, limited the diversity of species found. The concomitant reduction in competition and predation probably explains the relatively large numerical standing crop