The Fish of Jug Bay Patuxent River, Maryland A Pictorial Key

Transcription

1 The Fish of Jug Bay Patuxent River, Maryland A Pictorial Key Written by Doris Peters and Shannon Smithberger (December 99) Revised by Karyn Molines and Jeffrey Campbell (September 7)

2 Acknowledgements Over people have devoted many hours in the field netting and identifying fish during the Jug Bay fish survey. Although too many to list in this guide, the following contributed substantially to our knowledge of fish species of Jug Bay: Marty Barron Peter Bergstrom Jonathan Burns Jeffrey Campbell Eric Duce Kyle Maduro Woody Martin Doris Peters Bill Rodney Taj Rollins Tim Rule and Maryland Institute College of Art Vinnie Salamone Diana Smith Kathy Szlavacz, Dave Curson, and Johns Hopkins University Teon Wells Susan Wheatley Unless otherwise noted, fish illustrations are reproduced from the New York State Department of Environmental Conservation. ( for educational purposes only. White perch, inland silverside and Appendix A photographs by Jeffrey D. Campbell.

3 How to Use This Key This guide was designed to make it easy for those with little experience to identify most of the fish known to occur at the on the tidal Patuxent River. This key is easier to use than others since it avoids details such as the number of fins and the number of rays and spines found in most guides. Another advantage is that we have included only those species we have found during surveys or are likely to occur in Jug Bay. The key has descriptions and characteristics of these species. This identification key is based on more than 8 fish captured during surveys conducted between 987 and. This key separates fish species by () the number of dorsal fins, () the shape of the tail fin, () other characteristics including body color and mouth shape. Generally, the most frequently encountered fish are listed first. Start by examining the dorsal fin and tail to follow the key to the right section. Then use the pictorial keys and read the descriptions. Because we seine in shallow water, many of our fish are juvenile which lack adult characteristics and can be especially difficult to identify. Inspect dorsal fins carefully. Many species, for example the largemouth bass, are able to depress one dorsal fin making it appear as if they only have one rather than two dorsal fins. The average body lengths from our surveys are included along with graphs summarizing frequency of capture at each of the sampling locations. Maximum lengths are also provided for several species, based on information in Peterson's A Field Guide to Freshwater Fishes, 99. One dorsal fin, Round or broom-shaped tail Page 7 One dorsal fin Forked tail Pages 8 to Two dorsal fins separate Round or broom-shaped tail Page Two dorsal fins separate Forked tail Pages to Example Symbol Two dorsal fins joined Round or broom-shaped tail Page Two dorsal fins joined Forked tail Page

4 < % Capture Frequency Graphs The graphs show how frequently each species was caught at each location. The scale shows what percentage of all fish caught at the location was this species. The background color of the graph provides a clue as to how common they are captured during the study, the darker the color, the more often we capture the species. The horizontal axis represents the five different sites we monitor. These are coded with warm colors for tidal locations and cool colors for non-tidal. The vertical axis represents the percent abundance of this species compared to all the fish caught at the site. Background (frequency range) < % % % % % % Location Patuxent River () Otter Point () Beaver Pond () Two Run Creek () Pindell Creek () Eastern Mudminnow Example % range, so not very common anywhere. This fish is not found in the river. It is.% of the fish caught at Otter Point,.7% of the Beaver Pond,.9 % at Two Run and.% of the fish caught at Pindell Creek. References The following books were useful in preparing this key: Chesapeake Bay - A Field Guide, Christopher P. White, Tidewater Press, 989. Delaware s Freshwater and Brackish Water Fishes, Maynard S. Raasch and Vaughn L. Altemus, Sr. Delaware State College, 99. Life in the Chesapeake Bay, Alice Jane Lippson, The Johns Hopkins University Press, 98. Peterson's A Field Guide to Freshwater Fishes, Lawrence M. Page and Brooks M. Burr, Houghton Mifflin Company, 99. Fishes of the Chesapeake Bay, Edward O Murdy, Ray S. Birdsong and John A. Musick, Smithsonian Institution Press, 997. Guide to Freshwater Fishes of New York, Daniel Decker, Ronald Howard Jr, W. Harry Everhart, and John Kelly, Cornell Cooperative Extension Miscellaneous Bulletin 8, 98, reprinted 996. Freshwater Fish of the Carolinas, Virginia, Maryland and Delaware, Fred C Rohde et al., The University of North Carolina, 99. The following web sites contain information about many of the fish found at Jug Bay: Inland Fishes of New York (Online) Version., C.E. Kraft, D.M. Carlson, and M. Carlson, 6, Department of Natural Resources, Cornell University and the New York State Department of Environmental Conservation. Maryland Biological Stream Survey Fish Distributions, Maryland Department of Natural Resources, Pennsylvania Fishes, Pennsylvania Fish & Boat Commission, Freshwater Fishes of New York, New York State Department of Environmental Conservations.

5 General Parts of the Fish Explanation of Terms Used in Key Adipose fin A soft fleshy fin found behind the dorsal fin and in front of the tail. Found on catfish. Anterior The mouth end (front) of the fish. Barbel Whisker-like organ near the mouth. Dorsal Relating to the top (back) of the fish. Lateral Band A band of color present on the side of a fish. Lateral Line A row or line of sensory organs along each side of a fish, from head to tail, used for detecting vibrations, currents, and pressure. Posterior The tail end of the fish. Punctate Having tiny spots or points. Ventral Relating to the bottom (belly) of the fish. Mouth Types a. Terminal Mouth A mouth located at the anterior-most portion of the head. b. Upturned Mouth A mouth located above the anterior-most portion of the head c. Subterminal Mouth A mouth located below the anterior-most portion of the head.

6 Dichotomous Key to the Fish at A. Has a normal fish shape go to B A. Has an unusual fish shape, see page 6 including catfish American Eel (Anguilla rostrata)... 6 Least Brook Lamprey (Lampetra aepyptera)... 6 Hogchoker (Trinectes maculatus)... 6 Channel Catfish (Ictalurus punctatus)... 6 Brown Bullhead Catfish (Ameiurus nebulosus)... 6 B. Has one dorsal fin go to C B. Has two dorsal fins got to F C. Has a forked tail go to D C. Has a broom or round tail see page 7 Banded Killifish (Fundulus diaphanus)... 7, 7 Mummichog (Fundulus heteroclitus)... 7, 7 Mosquitofish (Gambusia holbrooki)... 7 Eastern Mudminnow (Umbra pygmaea)... 7 D. Has a normal mouth go to E D. Has a specialized moth see page Creek Chubsucker (Erimyzon oblongus)... Bay Anchovy (Anchoa mitchillia)... White Sucker (Catostomus commersoni)... Redfin Pickerel (Esox americanus)... Chain Pickerel (Esox niger)... E. Has smooth belly scales see pages 8 - Blacknose Dace (Rhinichthys atratulus)... 8 Rosyside Dace (Clinostomus funduloides)... 8 Creek Chub (Semotilus atromaculatus)... 8 Golden Shiner (Notemigonus crysoleucas)... 8 Spottail Shiner (Notropis hudsonius)... 9 Satinfin Shiner (Cyprinella analostana)... 9 Eastern Silvery Minnow (Hybognathus regius)... 9 Swallowtail Shiner (Notropis procne)... 9 Common Carp (Cyprinus carpio)... Goldfish (Carassius auratus)... Fathead Minnow (Pimephales promelas)... Fallfish (Semotilus corporalis)... E. Has saw-tooth belly scales see page Gizzard Shad (Dorosoma cepedianum)... Alewife (Alosa pseudoharengus)... Hickory Shad (Alosa mediocris)... American Shad (Alosa sapidissima)... Blueback Herring (Alosa aestivalis)... F. Dorsal fins appear separate go to G F. Dorsal fins are joined go to H G. Broom or round tail see page Tessellated Darter (Etheostama olmstedi)... G. Forked tail see pages - White Perch (Morone americana)... Striped Bass (Morone saxatilis)... Yellow Perch (Perca flavescens)... Inland Silverside (Menidia beryllina)... Largemouth Bass (Micropterus salmoides)... Smallmouth Bass (Micropterus dolomieu)... Spot (Leiostomus xanthurus)... H. Broom or round tail see page Bluespotted Sunfish (Enneacanthus gloriosus)... H. Forked Tail see page Pumpkinseed Sunfish (Lepomis gibbosus)... Bluegill Sunfish (Lepomis macrochirus)... Black Crappie (Pomoxis nigromaculatus)... White Crappie (Pomoxis annularis)... 6

7 One Dorsal Fin Round or Broom-shaped Tail Eastern Mudminnow - dark brown horizontal stripes Dark crescent at tail All fins rounded Terminal mouth Jug Bay average.7 cm Mosquitofish Rows of dots on tail Teardrop seen on older specimens Mouth upturned Dorsal fin starts behind anal fin origin Jug Bay average. cm Mummichogs and banded killifish are some of the most abundant small schooling fish in tidal wetlands. It is difficult to tell the females and young of both species apart. Female killifish have longer snouts relative to head size than mummichogs. Killifish, when viewed from above, are more streamlined. See Appendix A, page, 7 for distinguishing details Mummichog Chunky body, round tail Short snout, upturned mouth Male: Many silvery blue spots Female: Plain or with faint bars Young: Anal fin starts under dorsal fin Jug Bay average 6. cm maximum. cm Banded Killifish Stream-lined body, broom or fan tail Long snout, upturned mouth Male: Many wide silvery bars, breeding male has yellow throat and fins Female: Few narrow black bars Jug Bay average 6 cm maximum cm 7

8 One Dorsal Fin Forked Tail Blacknose Dace Dark lateral band is brown to black, pales with age Male has brick red sides during breeding season Brown with small scales and many small speckles Slightly downturned (subterminal) mouth Jug Bay average.9 cm Rosyside Dace Faint red slash just behind gill cover Upper side pale to dark with irregular blotches Lateral band from nose to tail Males have rosy sides during breeding season Terminal mouth Jug Bay average. cm maximum cm Creek Chub Black spot at dorsal fin origin Large terminal mouth Breeding male is pink with orange fins Immature resemble Blacknose Dace and Swallowtail Shiner. Look for dorsal fin spot and black band that goes across mouth. Jug Bay average 6. cm maximum cm Golden Shiner Silver or golden, lower fins can be orange or red Lateral line decurved (bends towards belly) Extremely compressed body No scales on keel Jug Bay average 8. cm maximum cm

9 One Dorsal Fin Forked Tail Spottail Shiner Fairly punctuate lateral line Spot on tail Large eye Silvery scales rub off easily Jug Bay average 6. cm Eastern Silvery Minnow Plain silver with nearly straight lateral line Young have purplish sheen on sides Large males are yellowish Jug Bay average 7. cm Satinfin Shiner Steel blue or gray with crosshatching Dark spot on rear of dorsal fin Males have white fins Jug Bay average.8 cm Swallowtail Shiner Strong punctuate lateral line which overlays black lateral band Color pale yellow with faint crosshatching above Black band from nose to tail, discontinuous at tail. Jug Bay average.8 cm 9

10 One Dorsal Fin Forked Tail Common Carp Golden brown color Large scales Long dorsal fin Short barbel on either side of mouth Introduced from Asia. Jug Bay average 9 cm maximum meter Goldfish Gold to olive-green to creamy white May have black patches Lacks barbels Introduced from Asia Fathead Minnow Thin diagonal lines over dark lateral band Faint dusky blotch on front of dorsal fin Breeding male: dark with black head, rows tubercles on snout, large white/gold blotch behind head and under dorsal Introduced from central US Jug Bay average cm Fallfish Dark crosshatching on silvery side Thick nose Jug Bay average. cm maximum cm

11 One Dorsal Fin Forked Tail These species are laterally compressed, lack lateral lines, and have sharply pointed belly scales which create a saw tooth s edge. Gizzard Shad Large purple-blue spot near gill cover in young and small adults Subterminal mouth; downward, rounded snout Long thread on dorsal fin, deep body Jug Bay average 7. cm maximum cm Alewife One spot Shallow body Distance between front of eye and tip of snout is less than eye diameter Jug Bay average. cm maximum 8 cm Hickory Shad Lower jaw extends well beyond upper jaw Dorsal fin trapezoidal in shape compared to American Shad American Shad Horizontal row of spots Deep body Triangular dorsal fin Jug Bay average 9. cm maximum 7 cm Blueback Herring Eye usually smaller than alewife Distinguished from Alewife by internal structures.

12 One Dorsal Fin Forked Tail Bay Anchovy Long jaw Huge mouth when pulled open Narrow silver stripe Body almost transparent Jug Bay average. cm maximum cm Creek Chubsucker Large, thick lips Ventral mouth for vacuuming invertebrates from the water. Anal fins attach to body at the posterior point of attachment of the dorsal fin. Dark blotches on bronze body Jug Bay average.7 cm maximum 6 cm White Sucker Blunt snout Silvery body Ventral mouth for vacuuming invertebrates from the water. Anal fins attach to body well posterior of the point of attachment of the dorsal fin. Jug Bay average.7 cm maximum 6 cm Duckbill-shaped Mouth with Sharp Teeth Chain Pickerel Teardrop nearly vertical Chain pattern Single dorsal fin located near the tail Jug Bay average.7 cm maximum 99 cm Redfin Pickerel Slanted teardrop extends below eye Reddish fins Single dorsal fin located near the tail Jug Bay average 7 cm maximum 8 cm

13 Two Separate Dorsal Fins Round or Broom-Shaped Tail Tessellated Darter Teardrop below eye X s and W s on side Often found resting at the bottom of streams on its large pectoral fins. Jug Bay average. cm Two Separate Dorsal Fins Forked Tail White Perch Dorsal hump Silvery body as in photo Anal fin begins near front of nd dorsal Lateral line arches up towards shoulder The dorsal fins of the white perch are actually joined but the deep notch between them gives them the appearance of being separated. Jug Bay average 9. cm maximum 8 cm Striped Bass Horizontal stripes in adults Young fish often have both vertical and horizontal stripes Anal fin begins in middle of nd dorsal Also known as the rockfish Jug Bay average 7. cm maximum meters

14 Two Separate Dorsal Fins Forked Tail Yellow Perch Males have orange fins Wide vertical dark bars on yellow or orange body Jug Bay average 8.7 cm maximum cm Inland Silverside Small first dorsal fin Bright silver band Picture shows first dorsal fin larger than it really is. Jug Bay average.8 cm maximum cm Largemouth Bass Gray to green color Blotches form lateral band Short st dorsal fin, separated Jaw extends beyond back edge of eye Introduced from other US regions Jug Bay average. cm maximum 97 cm Smallmouth Bass Brownish to brown, vertical bars Dorsal fins not completely separated Upper jaw does not extend beyond back edge of eye Scales on base of second dorsal and anal fins Spot One shoulder spot near gill cover - diagonal dark lines Long nd dorsal fin Jug Bay average. cm maximum 6 cm

15 Two Joined Dorsal Fins Bluespotted Sunfish Rows of silvery-blue spots on body and fins Jug Bay average. cm This is the only sunfish found in our area with a round tail. Round Tail Two Joined Dorsal Fins Pumpkinseed Sunfish Red or orange spot on black gill flap Wavy blue lines on lower jaw Orange and blue speckles near tail Jug Bay average 7. cm Black Crappie Sharp dip over eye Dark body, sometimes black with many silver spots Fins dark with circular transparent spots Widely introduced Jug Bay average 9. cm White Crappie Sharp dip over eye Gray or silvery body with faint bars Speckling on body and fins Dorsal fin further back than Black Crappie Jug Bay average 9. cm maximum cm Bluegill Sunfish Faint bars Blue cheek Spot or dark blotch on nd dorsal fin Widely introduced Jug Bay average. cm Forked Tail

16 Fish with unusual body features American Eel Normal mouth One continuous dorsal and caudal fin Jug Bay average. maximum cm Least Brook Lamprey Disk-like ventral mouth Notched dorsal fin joined to caudal fin Mouth parts distinguish from American Brook Lamprey Jug Bay average.7 cm maximum cm Hogchoker Lies flat on left side Appears surrounded by fins Dark on upper side, light on lower side Both eyes on right side No pectoral fins Jug Bay average.8 cm maximum cm Long Barbels Around Mouth The next two species have long barbels ( whiskers ) around the mouth and an adipose (fleshy fat deposit) fin on the dorsal side near the tail. Scales absent. Brown Bullhead Catfish Broom-shaped tail Jug Bay average 8 cm maximum cm Channel Catfish Forked tail Jug Bay average.7 cm maximum 7 cm 6

17 Female Appendix A: Comparison of Mummichog and Banded Killifish Mummichog Banded Killifish Male Head Top view Black spots in photographs are not distinguishing characteristics. Photos by Jeffrey D. Campbell 7