TPWD 1963 F-6-R-10 #887: Resurvey of Resaca de la Guerra: Fisheries Investigations and Surveys of the Waters of Region 5-B

JOB COMPLETION REPORT As required by FEDERAL AID IN FISHERIES RESTORATION.ACT TEXAS Federal-Aid Project No¢.F-6-R—10 .FISHERIES INVESTIGATIONS AND SURVEYS OF THE WATERS 0F REGION.5-B Job No. B-Zi _Resurvey of Resaca de la Guerra . Project Leader: Charles T. Menn H. D. Dodgen Executive Secretary Texas Game and Fish Commission Austin, Texas Marion Toole Eugene A. Walker . D-J Coordinator Director, Program Planning March 16, 1963 ABSTRACT The resurvey of Resaca de la Guerra, near Brownsville in Cameron County, Texas, revealed that catfishes and crappies are the most abundant game fishes presenta In netting collections, rough fish species, including alligator, spotted and longnose gars, gizzard shad, smallmouth buffalo, river carpsucker, carp, striped mullet, bluegill, freshwater drum and Rio Grande perch, comprised 73.5 per cent of the tOtal fish taken, Smallmouth buffalo and spotted gar were the first and second most abundant species both by numbers and weighta Over the years, siltation has caused the resaca to become progressively shallower, This has prevented the production of a substantial largemouth bass pOpulation, Furthermore, the abundance of bottom feeding rough fishes keeps the water murky, This makes bass feeding difficult or impossible and is reflected in the poor physical condition of largemouth bass, No evidence of the reproduction of largemouth bass was found, Water quality studies of the resaca indicate a suitable habitat for the survival and rapid growth of red drum (redfish)o One specimen of this species, captured in netting, weighed 15 pounds 2 ouncesa Apparently it entered the resaca as a juvenile in water pumped from the Rio Grande and grew to its large size within the resaca, Chemical renovation of the resaca is not recommended since it is presently impossible to prevent the entry of rough fishes from the Rio Grande. Efforts should be made to develOp biological controls for these fishes, In addition, fishermen should be encouraged to harvest more catfish and crappie, JOB COMPLETION REPORT State of Texas Project No, Fm6~Rm10 Name: Fisheries Investigations and Surveys of the Waters of Region S-B Job No, B~22 Title: Resurvey of Resaca de la Guerra Period Covered: June 15, 1962 through December 31, 1962 Objectives: To determine the relative abundance of the fish species present in the Resaca de la Guerra in order to formulate plans for fisheries development, Techniques Used: Fish populations in the Resaca de la Guerra were sampled with nets and seines from 24 netting and 24 seining stations (Figure 1), Net samples were collected with standard, 125~foot long gill nets constructed of nylon webbing, 8 feet deep, in five, 25~foot long sections of 1m, 1%-, 2-, 2%»,and 3-inch square mesh, The nylon seines measured 4— by 20~feet, with %-inch mesh, Netting and seining stations were visited monthly except that only 12 netting and 12 seining collections were made during June and December, Specimens taken from overnight net sets were weighed in grams and measured in millimeters, In addition to length and weight, sex, stage of gonadal development and incidence of parasites were recorded for each specimen, Seined specimens were preserved in 10 per cent formalin and were later identified and counted in the project laboratory, The common and scientific names of fish Species collected are listed in Table 1, Chemical analyses of surface water samples were not made each month as planned, however, twelve sampling stations were set up and analyses were made whenever possible, Two conferences were held with the Director, Water and Sewerage Division, and the General Manager, Municipal Public Utilities, City of Brownsville during the course of the study to obtain additional information concerning the resaca, Also, a number of informal discussions were held with interested persons owning land fronting on the resaca, as well as with sports fishermen, Findings: Introduction Resaca de la Guerra, also known as Resaca de las Palmas, is an enema n .cmw o mwmhmnsmv we Nm “seam consannaaa . afloenwmcm \\ weflflwbmnscnm mo humorAmv mxmunfi Hmeflm . [lastly we 0 mflmom : q:1:sj ..:;;Hmcmo ammo xxx HM Hmnmo momwnnmflnm gas AHV mnflwmono uecnum WM nowumum mflmmamn< acumz AW“ noH umum wanna,” cm H me .mHHmwSU NH @U monummm noflumum wnfluuwz @ avfiwwwfl G H canmwm Table 1a A List of Fish Species Recorded from Resaca de la Guerra Common Name : Scientific Name Alligator gar f Lepisosteus spatula Racépéde) Spotted gar : L, oculatus (Winchell) Longnose gar f L, osseu.s (Linnaeus) Threadfin shad ‘ Dorosoma pntenense (Gunt.her) Gizzard shad ? Q, cepediangm'CLeSueur) Mexican tetra i Astyanax mexicanus (Filippi) Smallmouth buffalo . .[ctiobus bubalus 1’Rafinesque) River carpsucker Ca.rpiodes c.a.rpio (Rafinesque) Carp _ Cyprinus carpgorLinnaeuE Tamaulipas Shiner ' NotroEis braytoniiJordan and Evermann} Channel catfish . Ictalurus punttatus (Rafinesque) Blue catfish - I, furcatus (LeSueur) Longnose killifish . Eggoulus ;ifliii§ (Baird and Girard) Gulf killifish 3 grandis Baird. and Gira:rd; Sheepshead minnow ' %yprinod.on variegatusiLacepede, Mosquitofish _ Gambugii‘gffinis (Baird and Girard) Sailfin molly Z Mollienesia‘lati inna~LeSueurE Amazon molly ; M fornrosa {Girardl Striped mullet ; Mugil cepha.lusl Linnaeus Tidewater silverside Menidia EEEXLABEE (COpe) White bass Roccus chrysops CRafinesqueE Largemouth bass - Microgteru.s salmoides (Lacepede) Warmouth Chaenobryttus gulosus (Cuvier) Redear sunfish : Lepomis micro lthus (Gunther) Bluegill L macrochlrus‘RafinesqueE White crappie Pomoxis annularis Refinesquej Black crappie P ni romaculatus (LeSueur) Freshwater drum . Aplodi 1.n.otus grunn1enisaf1nesqueE Red drum ; Sciaenogs ocellata (Linnaeus) Rio Grande perch 3 Gichlasoma cvano uttatum (Baird & Girard) Naked goby Gobiosoma DoscifiLacEpEdeE old stream bed of the Rio Grande which skirts a portion of the northern edge of the City of Brownsville, A limited survey and inventory of fish Species present in the resaca was made in 1958, The recent resurvey, however, is of broader scope in that more biological, Chemical and physical data were obtained, Physical Description The resaca heads northwest of the City of Brownsville where water, from two city owned pumps on the Rio Grande, enters the resaca.after flowing for about five miles in Open and underground canals, The Blemile long resaca -4- follows a winding, easterly course, north of the city, through virtually flat terrain and eventually flows into other resacas to the east of Brownsville. Because of the flat terrain, runoff is negligible. In the 12 miles of Resaca de la Guerra intensively studied during the resurvey (Figure l), the average width is approximately 60 feet and the average depth is less than 4 feeto Virtually all of the shoreline is privately owned, but the City of Brownsville has flooding easements for water storage, In addition to municipal and industrial use of water, home owners along the resaca are permitted to use water for their lawns, Consequently, water level fluctuations of 2 or 3 feet in 24_hours are not uncommon, Since the resaca is comparatively narrow and divided by road fills into short sections which are connected by one or two concrete pipes (Figure 2), it appears the high turbidity is due to the activity of bottom feeding fishes rather than wave actions Wave action due to wind is reduced by thick stands of huisache, retama, mesquite, palm and ebony trees along the shore- line (Figure 3)o Furthermore, the banks are sharply cut and rise about two feet on the average above normal water levelo In recent years, the production of citrus fruit and cotton in fields adjacent to the resaca has given way to private home develoPments, This, in turn, has limited public access to the resaca to road crossings. Fish Collections Netting m All told, 144 netting collections were made at 24 stations during the studyo All nets were set overnight at established stations, in water depths ranging from 1 to 6% feet, and were picked up the following morningo A total of 2,158 fish of 20 species, weighing 3,10906 pounds, was taken in the netting collections (Tables 2 and 3)o Rough fish including alligator, spotted and longnose gars, gizzard shad, smallmouth buffalo, river carpsucker, carp, striped mullet, bluegill, freshwater drum and Rio Grande perch accounted for 73.5 per cent of the fish collected and 8794 per cent of their weight, Smallmouth buffalos and spotted gars were the first and second most abundant species both by numbers and weightso Gizzard shad comprised only 403 per cent of fish taken in netting collections, and carp comprised only 208 per cent (Table 2)o .The relatively small numbers of gizzard shad may in part be attributed to the predation by gars and catfish, Surprisingly, gizzard shad, river carpsucker and carp comprise a relatively lower percentage of the fish population in the resaca than is normal for these species in waters of this area, It appears that this resaca is a more suitable habitat for smallmouth buffalo than for either the gizzard shad, river carpsucker or carpo Recent food habit studies by Dro W, W, Dalquest, of Midwestern University, reveal that the diet of the smallmouth buffalo consists mostly of animal life, whereas the diet of gizzard shad, river carpsucker and carp consists mostly of plankton and plant materialo Game fish species, including channel and blue catfish, white bass, F ig. 2. Drain pipes connect sections of Resaca de la Guerra. ___ - _- Fig. 3. A typical section of Resaca de la Guerra near Netting Station 3. “NIH wo.m mm.w @H.H @w.m mo.o mo.o mo.H mo.o mH.m nq.m o¢.HH mm.N mo.o mm.om 0N.¢ mw.o oo.ma Nm.o Monasz ha use Hw- m~¢uOH swan amuse swam mama swam wfimm wmuwownaH as mane muesfiafiw NH.moumofiwnH # «Hmnfioomn .NoaH umnfiw>oz Monouoo umnfiwumom umsmsm mash snow ...... uwnaooon smacks“ mosh .muuwsu ma mp mowmom .nmuwnfinnv mofiuuos Haww mo mufismwm manuOH. seesaw mom fiuuom mpfiwuw OHM Baum Houwaammnm **mfimmwno xumHm «romanwuo mums: Haammsam ssnmfimanw uwovom ssausofiuma #«mmwn susofiowumn «swamp songs uofiasa poaflnum «samwmumo mofim «anmfiwuwo Hoscwao memo Hoxoowaumo HmPHm oflwmmnn nusoaafimam moan pumnumw new wmoawcog new pwuuonm new nouwwfiafi¢ mowumnm i .N oHan isa.hm . o.aas.~ amam amsom . . .... ma mam memo mmumofl.nH rs %.Go moon was oo.oo~ o.moHnm m.MMH o.oo¢ «.mmm _ “.ma unou Ham mama Hmnamomn amaouau scam .muuoww ma on sawmom .mwfiwon aw .mfiwuuon HHHm mo muHSmwm meumoH.GH « meuOH Ennm mom sauna undone owm snap Hmumaamwnm #«owmnmno xowam snowmmmuo moans Haammaam sasmfimanm Hmopwm #«JuooEumB «smmmn auooawmumg «smmmn wanna umfiana pmafiuum «ssmwmuwu moan «aamuwuao assuage name waoswnumo Ho>wm onmmon ausoaafiwfim pmsm puwnuflw now omOGmmOA Hum uwuuomm How HouwmeH< mofiomnw .m magma ~8- largemouth bass, warmouth, redear sunfish, white crappie, black crappie and red drum comprised 26.6 per cent by number and 12.7 per cent by weight of the fish taken in-the nets. Since largemouth bass comprised only 1.4 per cent of the total number of fish taken in netting collections, and 0.7 per cent of their weight, it is apparent that the stocking of 1,500,000 largemouth bass in the .resaca since 1954 has not established a good pepulation. Collectively, channel and blue catfish comprised 14.9 per cent by number and 9.5 per cent by weight of the total netting_collections. Thus, catfish are the chief game fish species in the resaca. However, there is also a good crappie population in the resaca. Both white and black crappies were found. Collectively, they comprised 9.5 per cent of the total number of fish taken in netting collections. It is interesting to note that one red drum, or redfiSh, and one white bass were taken in the resaca. Apparently both fish entered the resaca via the canal system from the Rio Grande River. This belief is based on the fact that these fish were taken near the inlet from the river. If the red drum did come from the Rio Grande River, it is an almost certain .fact that the fish grew to its large size in the freshwater resaca. Table 4 shows the length and weight statistics for fish from the resaca. Table 5 shows the monthly results of gill_netting in terms of fish caught per net and per_foot of net. Seining _ Results of seining at the 24 stations are shown in Table 6. In all, 11,864 fish of 23 species were seined during the resurvey. Threadfin shad, bluegill and mosquitofish, in that order, were the most abundant and best distributed.species. The seining stations were selected with respect to habitat and were spaced as uniformly as possible along the resaca. Figure 1 shows the locations of the seining stations. Annotated Species List Alligator gag - Seven specimens, weighing a total of 56 pounds, were taken in gill nets during the resurvey. Based on the limited number caught and that they were taken at only four stations, it is apparent that the Species is not abundant in the resaca (Table 7). Analysis of stomach contents revealed unidentifiable fish remains in two stomachs and the remains of a snake in another. One of the specimens examined was parasitized with visceral round worms. Spotted gar w A total of-38l spotted gars was caught in gill net collections. Seven-others were taken in seines. The species was taken at 23 of the 24 netting stations and is the most abundant gar species in the resaca. Food items were found in spotted gar stomachs_in the following frequencies: unidentified sunfish remains - l3 stomachs, shad remains - 3