A Survey of Crayfishes, Aquatic Insects and Benthic Fishes of concern inhabiting the Sabine, Red, and Calcasieu River Systems in Louisiana Submitted to: The Louisiana Department of Wildlife and Fisheries 2000 Quail Drive, Room 439 P.O. Box 98000 Baton Rouge, LA 70898-9000 Submitted by: LSU AGRICULTURAL CENTER P.O. BOX 25071 BATON ROUGE, LA 70894-5071 __________________________ Michael D. Kaller Research Assistant Professor Renewable Natural Resources __________________________ William E. Kelso Professor Renewable Natural Resources Approved for Submission: _________________________ William B. Richardson, Chancellor and Chalkley Family Endowed Chair 2 Project Title: A Survey of Crayfishes, Aquatic Insects, and Benthic Fishes of concern inhabiting the Sabine, Red, and Calcasieu River Systems in Louisiana Principal Investigators: Dr. Michael D. Kaller, 225-578-0012, [email protected] Dr. William E. Kelso, 225-578-4176, [email protected] A. Raynie Harlan, 225-578-4071, [email protected] Tiffany E. Pasco, 225-578-4071, [email protected] School of Renewable Natural Resources 227 RNR Building Louisiana State University Agricultural Center Baton Rouge, LA 70803 Introduction Louisiana’s streams and rivers support extremely diverse and productive fish and invertebrate populations that provide the basis for important recreational and commercial fisheries to aquatic resource users. Perhaps more importantly, these populations are critical links in the aquatic food web and are important bio-indicators of lotic system health, which has become increasingly threatened during the last century from nutrient enrichment, habitat destruction and alteration, disruption of riparian zone function, excessive sedimentation, and invasion of exotic plants and animals, as outlined in Louisiana’s Comprehensive Wildlife Conservation Strategy (LACWCS 2005, p. 49). Louisiana is located at a biogeographically important nexus for invertebrates with one of the highest potential diversities in North America due to the overlap of the southern range of Neartic temperate species and northern extent of Neartic tropical species, specifically in the vicinity of 30o north latitude, and speciation on either side of the Mississippi River. These unique freshwater invertebrate assemblages provide ecosystem services not only in the immediate area but also to downstream rivers and estuaries. Aquatic Invertebrates and fishes improve water quality through biogeochemical cycling, and are important in linking terrestrial productivity and nutrient input to aquatic biomass and energy, and then reversing the nutrient and energy flow during insect emergence, providing a food source for not only aquatic species but terrestrial species as well (e.g., otters, raccoons and birds). Due to their physiology and reproductive strategies, these invertebrates and fishes have also become seriously threatened in the past century from increased siltation, degraded water quality, and pervasive habitat alterations, particularly regarding reduced inputs of woody debris as riparian zones have been cleared of their forest cover (LACWCS 2005, p. 48, 193). Louisiana’s lotic systems need to be effectively managed to maintain biodiversity and productivity, promote habitat diversity and function, and protect the quality and quantity of water that supports 3 Louisiana’s industrial, agricultural, municipal, and recreational interests. The number of streams on Louisiana’s 319-d impaired water body list attests to the continued impacts of land use activities on sediment deposition and water quality deficiencies. Knowledge of faunal assemblage composition and abundance in the state’s flowing water habitats can provide critical information that addresses all of these issues, and will yield baseline data for current, short-term assessments of ecosystem health, as well as evaluations of long-term changes in biodiversity, aquatic productivity, water quality, and habitat suitability. Project Need Conservation efforts directed at re-establishing or maintaining Louisiana’s aquatic biodiversity necessarily depend on accurate and comprehensive surveys of the present distribution and abundance of organisms inhabiting the state’s aquatic systems (LACWCS 2005). Louisiana has a diversity of bayous, streams, and rivers that exhibit substantial spatial and temporal variability in geomorphology, water quality, depth, flow velocity, substrate type, and habitat complexity, not only at an ecoregional scale, but also among and within the various lotic systems that comprise each of the state’s major watersheds. Implementation of a thorough and systematic sampling program can provide numerous benefits to aquatic resource managers, including distribution records, relative abundance estimates, habitat inventories, and water quality data. In particular, surveys can provide critical information on the current distribution and population status of rare, threatened, and endangered fishes and invertebrates, as well as other species that exhibit restricted distributions (at least based on past collection records) and may be of future conservation concern. Moreover, habitat and water quality information can be combined with fish and invertebrate distribution and abundance data to yield assessments of ecosystem impairment and potential mitigation strategies. A number of interesting freshwater organisms occur in the southwestern portion of Louisiana, which is primarily made up of the Western Gulf Plain and South Central Plains ecoregions (Figure 1). Many streams and rivers in this region flow through Western Pine Savannah and Western Xeric Sandhill Woodland habitats as well as seasonally wet prairies and agricultural lands with relatively low-elevation slopes. Of the 20 crayfishes included in Louisiana’s list of Species of Conservation Concern, 9 occur in the Calcasieu, Red, and Sabine drainages that flow through the western and west-central portions of the state (Table 1). Of the 28 fishes included in Louisiana’s list of Species of Conservation Concern, 6 likely 4 occur in the wadeable portions of these river systems (Table 2). Although there are many insects of concern on the state list, 11 aquatic taxa that can be identified with any confidence are likely to occur in the habitats we will be sampling in these streams (Table 3). Crayfishes often exhibit habitat associations based on stream structure and function, e.g., channel size, current velocity, substrate particle size, the abundance of allochthonous organic matter, and sufficient dissolved calcium for hardening their exoskeletons after molting. Fish species also tend to exhibit habitat associations that are based on stream size, including species mostly found in moderate sized tributaries (western sand darter, channel darter and bigscale logperch), and those that are more characteristic of smaller, headwater streams (bluehead shiner, sabine shiner, and suckermouth minnow). Aquatic insect distribution and abundance can be linked to a number of instream characteristics, including water quality, substrate composition, woody debris abundance, and the composition of the vertebrate and invertebrate predator assemblage. Because of differences in stream size and habitat complexity, a multi-gear sampling program is necessary to adequately determine present-day fish and invertebrate distributions and abundances. This proposal focuses on sampling programs in small streams, i.e., those that can be waded under base flow conditions and are amenable to shallow-water electrofishing and seining for fishes and crayfishes, as well as Hess sampling and woody debris collections for invertebrates. Our sampling program will therefore target small to moderate-sized streams in central and western Louisiana to determine the distribution and abundance of the species of concern listed in Tables 1-3, and will also generate date on habitat characteristics and water quality in the streams to assess habitat-biota associations and serve as baseline data for future studies. 5 Table 1. Crayfish species of concern that have been found historically found in wadeable portions of the Sabine, Red, and Calcasieu River systems. Concern denotes global (G) and state (S) ranks. Common Name Species Concern Pine Hills Crawfish Fallicambarus dissitus G4 – S2 Sabine Fencing Crawfish Faxonella beyeri G4 – S2 Calcasieu Painted Crawfish Orconectes blacki G2 – S1 Teche Painted Crawfish Orconectes hathawayi G3 – S3 Kisatchie Painted Crawfish Orconectes maletae G2 – S2 Southwestern Creek Crawfish Procambarus dupratzi G5 (should be G2/G3) – S2 Twin Crawfish Procambarus geminus G3G4 – S2 Caddo Chimney Crawfish Procambarus machardyi G1G2 – S1 Calcasieu Creek Crawfish Procambarus pentastylus G3 – S3 Table 2. Fish species of concern that have been found historically found in wadeable portions of the Sabine, Red, and Calcasieu River systems. Concern denotes global (G) and state (S) ranks. Common Name Species Concern Western sand darter Ammocrypta clara G3 – S2 Sabine shiner Notropis sabinae G4 – S2S3 Channel darter Percina copelandi G4 – S1S2 Bigscale logperch Percina macrolepida G5 – S1S2 Suckermouth minnow Phenacobius mirabilis G5 – S1 Bluehead shiner Pteronotropis hubbsi G3 – S2 6 Table 3. Aquatic insects of concern that may be present in wadeable portions of the Sabine, Red, and Calcasieu River systems. Concern denotes global (G) and state (S) ranks. Common Name Species Concern Hodges Clubtail Gomphus hodgesi G3 – S1 Pitcher Plant Spiketail Cordulegaster sarracenia G1 – S1 Texas Emerald Somatochlora margarita G2
Details
-
File Typepdf
-
Upload Time-
-
Content LanguagesEnglish
-
Upload UserAnonymous/Not logged-in
-
File Pages18 Page
-
File Size-