Great Basin Naturalist Volume 56 Number 4 Article 1 11-21-1996 Species-environment relationships among filter-feeding caddisflies (Trichoptera: Hydropsychidae) in Rocky Mountain streams Timothy B. Mihuc Idaho State University, Pocatello, Idaho G. Wayne Minshall Idaho State University, Pocatello, Idaho Janet R. Mihuc Louisiana State University, Baton Rouge Follow this and additional works at: https://scholarsarchive.byu.edu/gbn Recommended Citation Mihuc, Timothy B.; Minshall, G. Wayne; and Mihuc, Janet R. (1996) "Species-environment relationships among filter-feeding caddisflies (Trichoptera: Hydropsychidae) in Rocky Mountain streams," Great Basin Naturalist: Vol. 56 : No. 4 , Article 1. Available at: https://scholarsarchive.byu.edu/gbn/vol56/iss4/1 This Article is brought to you for free and open access by the Western North American Naturalist Publications at BYU ScholarsArchive. It has been accepted for inclusion in Great Basin Naturalist by an authorized editor of BYU ScholarsArchive. For more information, please contact [email protected], [email protected]. The Great Basin Naturalist PUBLISHED AT PROVO, UTAH, BY BRIGHAM YOUNG UNIVERSITY [SSN 0017-3614 VOLUME 56 31 OCTOBER 1996 o. 4 Great Basin Naluralist 56(4), © 1996, pp. 287-293 SPECIES-ENVIRONMENT RELATIONSHIPS AMONG FILTER-FEEDING CADDISFLIES (TRICHOPTERA: HYDROPSYCHIDAE) IN ROCKY MOUNTAIN STREAMS TImothy B. Mihuc1,2, G.Wayne MinshalJ!, and Janet R. Mihuc3 ABSTRACT.-Species-enviTonmenl relationships were determined fOT filter-feeding macroinvertebrates from 55 Rocky Mountain stream sites to establish species distribution patterns. Species abundance and 20 environmental vari­ ables were measured at each site with species-envkonment relationships determined using canonical correspondence analysis and stepwise multiple regression. Results suggest that the distribution of several taxa was strongly related to upstream-downstream environmental gradients. ArctOPSYCM grandis abundance increased with stream size (width and depth) and decreased with increasing turbulence (Reynolds number). Brachycentru.s abundance also increa~ed with stream sire {depth). Hydropsyche abundance increased with increasing ba.seflow. PMapsyche elsis abundance demon­ strn.ted negative correlation with depth, Froude number, and conductivity. Taxa followed previously reported patteros, partitioning habitat according to stream size. Arctopsyche grandis, Brachycent1'W. and Hydropsyche were found in larger (3rd- to 6th·order) streams, while P(Uapsydut elsis was obseT\led in small headwater (lst- and 2nd-order) streams. Other filter-feeding taxa such as Stmulium, Pisiditml, and ostracods exhibited little or no apparent habitat partitioning among stream sites. Key lJ)cm:ls: species-environment relationships. fJter feeders. Rocky Mountain streams. Benthic macroinvertebrates adapted for re­ Minshall 1990, Richardson and Mackay 1991). moving particles from suspension (filter feeders) Many studies have determined filterer associa­ are an important component ofstream commu­ tions with food resources and environmental nities. Distribution patterns and habitat associ­ factors such as water velocity or temperature ations among 6lterers have been well docu­ (e.g., Edington 1968, Wallace 1974, Haddock mented, particularly for members of the Tri­ 1977, Wallace and Merritt 1980, A1stad 1982, choptera family Hydropsychidae (e.g., Decamps Hauer and Stanford 1982, Bruns et al. 1987, 1968, Edington and Hildrew 1973, Gordon Osborne and Herricks 1987, Wetmore et. al. and Wallace 1975, Wallace and Merritt 1980, 1990, Voelz and Ward 1992). Few studies have Ross and Wallace 1982, Tachet et al. 1992) and considered the entire filterer component found for lake outlet communities (e.g., Robinson and in natural (unimpounded, unregulated) streams lStream Ec¢logy Center, Dep,u:tment of Biological Sciences, ld.bo State University, Pocatello. ID 83209-8007. 2PreW(lt addl'e~: Loui.suUla Coopenttive Fhberies and wildHre R~-oo. Unit, School of Fore~tty, Wildlife and FI~he'ies. Lo"i>;iana State Unive""ity. Bat,," Rooge, LA 7Q8OJ. 3.Biology Prog,rllm, 104 Ufe Sc.ienl:e$ Buildins. Louis:illJla Stille Unive,-,ity. Baron Roug¢. LA 70803. 287 2.88 GREAT BASIN NATUJIAUST [Volume 56 and distribution pattems of filterer species as temperature at the time of sampling) and with respect to a wide range of environmental minimum temperature (the freezing point of variahles (Edington and Hildrew 1973, Gordon water). Water chemistry variables included and Wallace 1975, Boon 1978, Ross and Wal­ hardness, alkalinity, pH, and specific conduc­ bee 1982). OUf objective was to assess the dis­ tance. Other biotic variables measured at each tribution patterns of filter feeders in unim­ stream reach were chlorophyll a (n = 5 per pounded Rocky Mountain, USA, streams to site), ash-fi·ee dry mass (AFDM) of periphyton determine relationships with specific environ­ (n = 5 per site), biomass/chlorophyll ratio of menlill variables includin~ flow parameters; periphyton (B/C), and benthic organic matter stream size, depth, and width; benthic organic content (BOM; 11 = 5 per site). This study did matter content; slope; water chemistry; peri­ not address food resources or food acquisition phyton hiomass; and temperature. \,Vhile many among filte.. feeders; therefore sampling of studies have considered current velocity, tem­ transported and henthic nne particulate mater­ perature, <Jnd food relationships, partitioning ial was not included in sampling protocol. of habitat by IUter feeders in rclation to other Relationships between species and environ­ environmental variables is poorly known. mental variables were determined using canon­ ical correspondence analysis (Ter Braak 1986) METHODS and stepwise multiple regression. All compar­ isons ,\'ere made on reach-scale data (reach Stream siles encompassed the Rocky Moun­ means for all variables). Comparisons reflect lain region ii·om nurthern Wyoming to c-entral spatial diAerences among sites sampled in 1 Idaho, including 2.2. streams in Yellowslone season (summer) to determine hrge-scale distri­ National !'lu·k and 33 ill centml Idaho. Streams hution patterns offilter feeders in 1st- through ranged from 1st to 6th order in size (Tahle 1). 6th-order streams. Temporal patterns were not All sites were unimpounded and none were considered here. Canonical correspondence located below lake outflows. Yellowstone sites analysis (CCA) allows the investigator to inter­ were sampled each August /i·om 1988 to 1992.. pret multiple species responses along a gradi­ All other sites were sampled heh~!een July and ent of multiple environmental variables. This September during the ycar(s) indicated in analysis provides a useful interpretation of lable 1. Sampling methods were routine meth­ species-enviromnent relationships through the ods nsed in stream ecology (e.g., Platts ct al. resulting ordination plot. Once species~envi­ 1983). Briefly, henthic organisms were sam­ ronment eonelations were identified using plcd using a surher net (2.50 micron mesh) in CCA, multiple regression analysis was used to lime habilat at 5 tr,Ulsects located at 50-m inter­ further discern relationships between species vals along a stream reach (2.50 m total reach abundance and environmental variables. length). Samples were taken to a depth of 10 em. Mean density for each flItcrcr species \vith­ RESULTS in each stream reach \vas lIsed in statistical In the canonical correspondence analysis analyses to determine relationships with physi­ (Fig. 1) thc Ilrst ordination axis (x axis) ex­ cal variahles. Physical environmental variables plained 37.9% ofthe total species-environment measured. at each st.ream reach included stream relationship and the second (y axis) an addi­ order, slope, width, baseflow (1 transect), mean tional 30.7% (Table 2.). Results indicate that depth (n = 100 random measurements), m",m several envi.ronmental variables were impor~ water velocity (n = 100 random measurements), tant in explaining variation in species abun­ mcan embeddedness (11 = 100 random mca­ dance across sites (Fig. I). Arctopsyche grandis surements), and mean suLsh1tte size (n = 100 and Hydropsyche abundance related directly random measurements). Reach-scale means for to increasing baseflow, width, and stream order all variables were used in statistical analyses. (Fig. 1). Parapsyche elsi' abundance was inverse­ Width/depth ratio and scvcral hydraulic para­ ly related to increasing baseflow, width, and meters (mean Fronde numhel; mean Reynolds stream order. Brachycentnvs abundance related number) were calculated f.·om these measure­ primarily to depth, substrate size, .Reynolds ments. Annual sh'eam tcmpcmture range was number, and annual tempemture range (Fig. I). estimated from annual maximum (estimated Simuliwn, PiSidiu.f11.. and Ostracoda abundance 1996] FILTER-FEEDING 1NVERTERRATES IN ROCKY MOUNTAJN STREAMS 289 TABLt: L SummUlY ofthe 55 study streams. Sites are arranged by increasing stream order and tncrc:L'iLlig depth witbiu each order. Slrea". Sample dates Order Avg Avg Basellow Slope depth (m) width (m) (m/s) (%) Cach~. YNP 1988-1992 I 0.06 0.704 0.003 L2 E Blacktail Dt:!er, 'iN P 1988-1992 1 0.13 0.665 0.048 4.7 Twin, YNP 1988-J99'2 1 0.13 0.643 0.06 10.7 W Blacktail Deer, YNP 1988--1992 1 0.17 0.550 0.043 3.S F<l.iry. YNP 1988--199-2 I 0.23 0.307 0.066 1.0 Pinneer, ID 1990 2 0.05 0.342 0.13 6 DllltOO, 10 1990,91 2 0.06 0.109 0.07 17 Goat. 1D 1!Jl.X},91 2 0.06 0.089 0.05 18 Cache, y~p 1988--1992 2 0.09 0.764 0.012 10.1 Packhorse, ID 1991 2 0.09 0.4t3 0.04 4 Castle, 10 1992 2 0.09 0.160 0.03 U.5 Yellow, ID 1992 2 0.09 0.220 0.03 8 Rose, 'iN!' 1988-1992 2 0.10 0.416 0.027 7.S Sliver, IV 1991 2 0.10 0.243 0.04 5 EF Whimslick, ID 1991 2 0.10 0.460 0.02 2 Cache. YI\P 1988-1992 2 O.ll 0.832 0.012 8.8 Cliff, to 1988,90,91 2 0.12 00407 0.18 L2 Amphith~,tcr, Y:-.IP 198B---lOO2 2 0.13 1.11 0.146 4.9 POll)'. ID 1992 2 0.13 0.380 008 13 Iron Springs, YNP 1988---1992 2 0.14 0.237 0,1)38 13.1 E McCall.