Saturday, December 29, 2018

Fluvial Fishes Lab Year in Review

New Year’s Day… now is the accepted time to make your regular annual good resolutions. Next week you can begin paving hell with them as usual.”  Mark Twain
Many of my good intentions were realized in 2018.  The year ended with the delivery of the completed layout for the Field Guide to Freshwater Fishes of Virginia to Johns Hopkins University Press.  Six coauthors (Paul E. Bugas, Jr., Corbin D. Hilling, Val Kells, Michael J. Pinder, Derek A. Wheaton, and Donald J. Orth) developed this up-to-date field guide to all the freshwater fishes of Virginia.  The guide contains in introduction to the study of Virginia's freshwater fishes, a key to the families, 175 color illustrations, 29 color photos, illustrations of diagnostic characteristics, range maps, descriptions of the 225 species of freshwater fishes, glossary, and index.  If you need to know what fish is also called the "Gaspergou," you can find the answer in this guide.  Many fish facts are included in the species accounts and species newly discovered are included.   Other publications are listed below along with several favorite blog posts and photos from Ichthyology class.

Poster presentation on Field Guide to Freshwater Fishes of Virginia.  Click for link.
Publications for 2018

Bugas, P.E., Jr., C.D. Hilling, V. Kells, M.J. Pinder, D.A. Wheaton, and D.J. Orth. In press. Field Guide to the Freshwater Fishes of Virginia. Johns Hopkins University Press, Baltimore, Maryland.  expected Sept. 2019.

Carey, C.S., D.J. Orth, and V. Emrick. 2018. Biological Surveys for Fries Hydroelectric Project in the upper New River, Grayson County, Virginia. Final Report to TRC Solutions, Reston, Virginia.  Conservation Management Institute, Department of Fish and Wildlife Conservation, College of Natural Resources and Environment, Virginia Polytechnic Institute and State University, Blacksburg, VTCMI-04-2018.  65 pp. 

Fries Dam, Fries, Virginia, at low flow.  Photo by D.J. Orth.
Dickinson, B.D., S.L. McMullin, D.J. Orth, and J.R. Copeland. 2018. Trotline catch rates vary by hook and bait type in the New River, Virginia. Journal of the Southeastern Association of Fish and Wildlife Agencies.  5:46-52.
Hilling, C.D., S.L.Wolfe, J.R. Copeland, D.J. Orth, E. M. Hallerman. 2018.   Occurrence of two non-indigenous catostomid fishes in the New River, Virginia. Northeastern Naturalist 25(2):215-221.  DOI: 10.1656/045.025.0204     Link to DNA Barcoding video.

Hilling, C.D., A.J. Bunch, R.S. Greenlee, D.J. Orth and Y. Jiao.  2018. Natural mortality and size structure of introduced Blue Catfish in Virginia tidal rivers. Journal of the Southeastern Association of Fish and Wildlife Agencies 5:30-38.

Moore, M.J., and D.J. Orth. 2018. Stories worth sharing.  Fisheries  43(12):575-576.   Link to Michael J. Moore video story My Dog Ate My Lab Notebook. 

Moore, M.J., D.J. Orth, and E.M. Hallerman. 2018. Multi-metric conservation assessment for the imperiled Clinch Dace. Southeastern Fishes Council Proceedings 58:31-56.

Orth, D.J.  2018.  Social media may empower fisheries students via learning networks.  Fisheries  43(3):130-138.

Orth, D. 2018. Learning lessons about Lampreys.  American Currents 43(3):11-16.

Orth, D.J. In press.  Socrates opens a Pandora’s box of Northern Snakehead issues. Pages 000-000 in D. Chapman and J. Odenkirk, editors.  First International Snakehead Symposium, American Fisheries Society, Bethesda, Maryland.

Schmitt, J.D., B.K. Peoples, L. Castello, and D.J. Orth. 2018. Feeding ecology of generalist consumers: a case study of invasive blue catfish Ictalurus furcatus in Chesapeake Bay, Virginia, USA. Environmental Biology of Fishes DOI: 10.1007/s10641-018-0783-6

Stang, S.A., C.D. Hilling, and D.J. Orth. In press.  Lessons learned from 35 years of students organizing the Mudbass Classic. Fisheries  44

Outreach for 2018 

Joseph Schmitt defended his dissertation and moved on to a position as Fisheries Research Biologist with the USGS investigating Lake Erie fisheries.  Corbin Hilling was awarded a 2-year Virginia Sea Grant Fellowship to further his studies of the nonnative Blue Catfish in tidal rivers.    See news release.
Corbin Hilling, doctoral student, received Virginia Sea Grant Fellowship in 2018.
There are new writings and activities on the outreach front. Stories about the non-native catfish appear regularly in a blog, managed by PhD student, Corbin Hilling, and Joseph Schmitt, PhD.  The most recent was an interview with Captain John a recreational fishing guide for Blue Catfish on the James River.  See ChesapeakeCatfish.   Corbin Hilling recently taught a group of young 4-H students about fishes (see below) and Don Orth taught Master Naturalists in the Southwest Piedmont chapter about the fishes of Virginia.   With Dan Goetz and Aaron Bunch of the Virginia Department of Game and Inland Fisheries, we organized and presented a Continuing Education session on Field Sampling Design and Statistical Power. 
My lab coat was decorated with Gyotaku by a group of young students. Photo by D.J. Orth.
Illustration of the Atlantic cutlassfish, or ribbonfish, Trichiurus lepturus (above) and student's model (below).  Photo by Corbin Hilling. 
Don Orth after presenting paper at Virginia Chapter AFS meeting in Fredericksburg, Virginia. Photo by Valerie Orth
The #25daysofFishmas hashtag on Twitter celebrated Great Lakes Fishes, thanks to Katie O'Reilly, who organized daily tweets since 2016. The Virginia Tech Ichthyology Facebook group joined in for 2018.  You may follow the fishes highlighted for each of the 25 days of Fishmas, starting with the Mahi Mahi.   

Photos from Ichthyology 2018 

Species of Petromyzontidae in Virginia.  Photo and illustrations by Hanna Infanti.
Students dissect a Walleye collected from New River. Photo by D.J. Orth.
Learning to distinguish the Moxostoma is given more than lip service.  Photo by Taylor Comer

Pharyngeal arch removed from a minnow. Photo by Jared Rodenas.
Fish memes help us remember scientific names. Photo by D.J. Orth.
Cheers to 2019!  If interested, follow our blog,  join Virginia Tech Ichthyology on Facebook and/or follow Fluvial Fishes Lab on Twitter @donaldorth

Tuesday, December 18, 2018

Are Your Sardines Seabird Safe? by Don Orth

Seabirds are the most threatened group of birds (IUCN 2018). Major threats relate to fisheries bycatch and competition. Fishing occurs on more than 55% of ocean area and has a spatial extent more than four times that of agriculture (Kroodsma et al. 2018). This fisheries footprint estimate is made possible by the automatic identification system required on marine vessels for tracking.  Long line (45%), purse seines (17%), and trawls (9.4%) are the three most widespread forms of ocean fishing. Impacts of fishing go well beyond the species targeted for harvest. Bycatch effects are obvious, but industrial fisheries are also implicated in starving seabirds (Grémillet et al. 2016). Recent evidence shows that fisheries compete with seabirds by taking the same fishes, a limited resource, and the take has fitness consequences for seabirds. There is no such thing as a free lunch, or a tuna sandwich that does not have seabird consequences.  
Global footprint of fishing coverage.  From Kroodsma et al. (2018).
Gremillett et al (2018) reconstructed global fisheries catches since 1970 to compare with seabird diets. Global harvesting reduced abundance of fish eaten by many seabirds and competition was identified in 48% of all areas, notably the Southern Ocean, Asian shelves, Mediterranean Sea, Norwegian Sea, and Californian coast.  The decrease primarily occurred in the Southern Ocean and in the North Atlantic and was most marked in diving petrels (−66%), terns (−48%), and frigatebirds (−47%).

Competition with fisheries significantly constrains a vanishing seabird community. from Grémillett et al. 2018.

Calls for changes in fisheries management goals began over 40 years ago. Larkin wrote this epitaph for the Maximum Sustained Yield concept (MSY) in 1976 and  OSY, or optimum sustained yield, was the logical successor.  OSY is the deliberate melding of social, economic and biological benefits. Among these many benefits, we seek a unique management goal exists for each fishery that balances the many conflicting goals.  One of the benefits relates to seabirds.  And herein lies the challenge. 


Here lies the concept, MSY.
It advocated yields too high,
And didn’t spell out how to slice the pie.
We bury it with the best of wishes,
Especially on behalf of fishes.
We don’t know yet what will take its place,
But hope it’s as good for the human race.


M.S.Y. is still alive and kicking.  However, major databases such as the Data Seabird Information Network, launched by the World Seabird Union, and Tracking Ocean Wanderers database, maintained by BirdLife International can assist in detecting decreasing seabird population trends. We need to get beyond observations, such as this Arctic tern (Sterna paradisaea) eating a sandeel and apply ecosystem-based fisheries management models that consider data on abundance of non-target ecosystem components, including pinnipeds, orcas, seagrasses, cownose rays, whales, cephalopods, and more (Pikitch et al. 2014).  In the mid-Atlantic region we might manage Atlantic Menhaden harvests and protect some menhaden for consumption by Striped Bass, Humpback Whales, and Bluefin Tuna. Black Skimmer, which have declined, also eat Atlantic Menhaden (Gordon et al. 2000) - but how much?  However, the trophic models used for these analyses (Pikitch et al. 2014) make assumptions that need to be tested. Evidence that harvesting forage species competes with other top predators in well-studied US fisheries is equivocal (Hilborn et al. 2017).  
Black-footed Penguin (Spheniscus demersus) pair hunting sardines, Cape Town, South Africa. Photo by Peter Verhoog.
Globally, competition with fisheries should be assessed as one of the numerous stressors acting upon the fitness of individual seabirds, and population trajectories (Grémillett et al. 2016; Lescroël et al. 2016).  It won't be easy to do.  To assess seabird-fisheries competition, we can design and implement localized prey depletion experiments and work to improve the trophic models of intermediate complexity (Sydeman et al. 2017).  No one wants to hear that a lot more research will be needed.
Gannet eats a mackerel.  Photo by Rob Ellis. Flickr
For more sustainable food systems, we should eat less livestock and more seafood low on the food chain (Hilborn et al. 2018).  However, not all fisheries operate in a sustainable manner. To convince consumers to eat sustainable seafood, we need reliable means for evaluating and labeling marine products.  You won’t find a 'seabird safe' label at your seafood market. But how does one know?   That’s the subject for another post.


Amélineau F. Fort J. Mathewson P.D. Speirs D.C. Courbin N. Perret S. Porter W.P. Wilson R.J. Grémillet D. 2018. Energyscapes and prey fields shape a North Atlantic seabird wintering hotspot under climate change. Royal Society Open Science 5: 171883
Gordon, C.A., D.A. Cristol, and R.A. Beck. 2000.  Low reproductive success of black skimmers associated with low food availability.  Waterbirds: The International Journal of Waterbird Biology 23:468-474.
 Grémillet D. Péron C. Kato A. Amélineau F. Ropert-Coudert Y. Ryan P.G. Pichegru et al. 2016. Starving seabirds: unprofitable foraging and its fitness consequences in Cape gannets competing with fisheries in the Benguela upwelling ecosystem. Marine Biology 163: 35
 Grémillett,D.,  A. Ponchon, M. Paleczny, M-L. D. Palomares, V Karpouzi and D. Pauly. 2018. Persisting worldwide seabird-fishery competition despite seabird community decline. Current Biology 28:1-5.
 Hilborn, R., R.O. Amorosa, E. Bogazzi, O.P. Jensen, A.M. Parma, C. Szuwalski, and C.J. Walters.  2017.  When does fishing forage species affect their predators?  Fisheries Research 191:211-221.
Hilborn, R., J. Bonobi, S.J. Hall, T. Pucylowski, and T.E. Walsworth.   2018. The environmental cost of animal source foods. Frontiers in Ecology and the Environment 16(6):329-335.
IUCN 2018. The IUCN Red List of Threatened Species, Version 2018-2.
Kroodsma, D.A., et al. 2018. Tracking the global footprint of fisheries. Science 359:904-908.
Larkin, P.A. 1977. An epitaph for the concept of maximum sustained yield. Transactions of the American Fisheries Society 106:1-11.
Lescroël, A., R. Mathevet, C. Peron, M. Authier, P. Provost, A. Takahashi, and D. Grémillet, D. 2016. Seeing the ocean through the eyes of seabirds: A new path for marine conservation? Marine Policy 68:212–220.
Pikitch, E.K., and nineteen coauthors. 2014. The global contribution of forage fish to marine fisheries and ecosystems. Fish and Fisheries 15(1):43-64. doi:10.1111/faf.12004
Sydeman, W.J., S.A. Thompson. T. Anker-Nilssen, M. Arimitsu, A. Bennison, S. Bertrand, P. Boersch-Supan, C. Boyd, N.C. Bransome, R.J. Crawford et al. 2017.  Best practices for assessing forage fish fisheries-seabird resource competition. Fisheries Research 194:209-221

Friday, November 16, 2018

Let's Write More Engaging Stories, by Don Orth

When students ask for my advice or tips for success, I provide a long list of technical skills and certifications that will help them stand out in the crowd of young scientists – scientific diving, electrofishing, safe boating, engine repair, OSHA, R, Illustrator, JAGS, Python, microscopy, and sensor calibration. “These things will look great on your C.V.” I tell them. But no matter your specialty, we all will need superb communication skills, a network, and relationships to make sure you realize your dream.  Here I highlight some favorite ideas for communicating science and nurturing a network. When Voltaire penned “The perfect is the enemy of the good,” he may have been speaking to why we are inhibited from writing for a public audience.   Building communication skills requires many attempts to communicate and frequent reactions, such as “What do you mean?”

In the Department of Fish and Wildlife Communication, we have long required graduate students to translate their thesis findings to a form for a non-scientific audience. My first graduate students shared aspects of their studies in Virginia Wildlife (Leonard and Orth 1985; Graham and Orth 1986; Austen and Orth 1988).

Scientists in fisheries management and conservation sciences must be capable of communicating with non-scientists. Our poor communications training is a long-standing issue and affects many professions.  Physician and author, Michael Crichton, authored an article in 1975 entitled “Medical Obfuscation: Structure and Function” in The New England Journal of Medicine.  In this article he lamented the impenetrable writing skills of most physicians.  

Start with your message, develop convincing prose, and adapt it to your specific audience.  Many resources are available to assist you.  Begin with the Compass website. The message box is a simple tool to help you distill your message.  Like others, I tend to write too many details when communicating with a non-scientific audience.  If I am empathetic to their needs, I must make meaning in the fewest and simplest words possible.   

Randy Olson, author of Houston We Have a Narrative, provided a template for creating engaging stories.  The acronym, ABT, reminds one that "AND" sets up the background, "BUT" identifies the problem and conflict, and "THEREFORE" describes one solution to the conflict.  Listen to sciencecommunicator, Tullio Rossi, explain how to turn your science into a captivating story.

Comic designed to contrast the typical science presentation with a more engaging story that uses the And, But, Therefore template.

Consider these simple steps for making your message more shareworthy (from Moore and Orth 2018).

·      Trust your story and adapt the ABT framework.
·      Avoid getting sidetracked by unnecessary details. Place difficult to understand concepts in terms the audience understands with analogies.
·      Relay the human element of the story that includes your emotions and the sensory details that can help the reader engage.
·      Be self-deprecating and find the humor in your mistakes. Your audience is more likely to see you as relatable and trustworthy, rather than depressing and whiny.
·      Use a variety of media. Alternatives to journal impact factors for gauging research influence now account for the power of social media to communicate science with services, such as Plum Analytics and Altmetrics.
·      Bolster your stories with photos, music, video, or art. Turn it into a children’s picture book.
·      Take advantage of free or inexpensive platforms, including Twitter, Facebook, Instagram, Snapchat, blogging platforms, and YouTube.

Contrasting presentations for scientific and public audiences.
At a recent plenary talk at the AFS  meeting in Atlantic City, Dr. Christine O’Connell (Alan Alda Center, Stony Brook University) emphasize three messages for making your voice matter and making your science count.    

Takeaway 1. SHIFT YOUR FOCUS: It’s not about you, the listener must catch the message. Pay attention to your audience
Takeaway 2. FOSTER EMPATHY: We must deal with the curse of knowledge and avoid jargon.
Takeaway 3. TELL A STORY:   Stress the meaning and not the details in a way that makes the listener care.  

There are many stories we need to tell and our pre-occupation with statistical significance often stifles our creative storytelling.  Ditching the jargon is a most common recommendation from experienced science communicators (Helmuth 2012; AGU 2018; Merkle 2018; Quinlan 2018).

You should share the lessons learned from the non-significant findings of your investigations (adapted from Moore and Orth 2018).
It’s never too early to begin teaching basics of communication, whether in elementary middle or high school or college.   It takes practice and instructors should dispense with multiple choice exams and require authentic forms of communication.  Students needs guided practice with video, photography, sound, text and social media for messaging across multiple platforms.  I have converted some essays in exams to infographics or digital video essays.   Adolescents today spend more time composing unique genre restricted to 280 characters on Twitter via their mobile phones (2017).  My students write blog posts in addition to scientific articles, for example, check out Chesapeakecatfish, ClinchChronicles, VT Ichthyology, and The Troutlook.  Saunders et al. (2017) suggest that blogging can have broad benefits in developing professional networks, collaborations, and sharing the essential scientific papers.  

Storytelling is sometimes great for conveying your less successful moments as a scientist.  Lessons learned from mistakes are popular ways to engage non-scientists in the nitty-gritty aspects of our work.  Consider, for example, the success of Jim Jourdane’s Fieldwork Fail: The Messy Side of Science! So write more, and when you do make your writing more engaging.


American Geophysical Union (AGU). 2018. Jargon and how to avoid it.  Accessed November 16, 2018 from

Austen, D. J., and D. J. Orth.  1988.  Sampling of waters with electricity.  Virginia Wildlife 49(4):24-27.

Crichton, M. 1975.  Medication obfuscation:  structure and function.  The New England Journal of Medicine 293:1257-1259.  Accessed November 16, 2018 from

Graham, R. J., and D. J. Orth.  1986.  Living in the danger zone.  How do smallmouth bass survive?  Virginia Wildlife 47(4):22-25.

Helmuth, L.  2012.  Pitching Errors: How Not to Pitch. The Open Notebook.  Accessed November 16, 2018 from

Leonard, P. M., and D. J. Orth.  1985.  Are your streams healthy?  Ask the fish!  Virginia Wildlife 46(4):14-17.

Quinlan, C. 2018. Ditch the Jargon, Change the World? Science 37 Trial Mix website.  Accessed November 16, 2018 from

Merkle, B. G. 2018 Tips for Communicating Your Science with the Press: Approaching Journalists.  Bulletin of the Ecological Society of America 99(4):e01430.

Moore, M.J., and D.J. Orth. 2018. Stories worth sharing.  Fisheries.  

Saunders, M.E., M. A. Duffy, S. B. Heard, M. Kosmala, S. R. Leather, T. P. McGlynn, J. Ollerton, A. L. Parachnowitsch. 2017. Bringing ecology blogging into the scientific fold: measuring reach and impact of science community blogs. Royal Society Open Science   4: 170957.

Warner, J. 2017. Adolescents’ New Literacies with and through Mobile Phones. Peter Lang International Academic Publishers. New York. 198 pp.


Monday, August 13, 2018

Sunfishes (Lepomis) of Virginia, by Don Orth

Centrarchid fishes exist only in North American freshwaters and are well known as popular sport and aquarium fishes.  There are 38 species in eight genera, all of which may be identified by a laterally compressed body, two connected spiny and soft dorsal fins, spines on anal fins, and pelvic fins in a thoracic position.  The most diverse genus is Lepomis, commonly referred to as the sunfishes in recognition of their highly colored breeding colors.  These colorful sunfish are often the first fish caught and remembered by a young angler.  Their importance in sustaining American sport fisheries cannot be overstated.    Virginia has eight species of Lepomis, but there are thirteen in North America (Warren 2009).  Explore this link to a gallery of photos of Lepomis.  

Due to the popularity as a sport fish, sunfish are widely introduced throughout North America and even in other continents.  The body form and habits all support a generalized sight-feeding habit on a variety of crustaceans, insects, and small fishes. Males develop bright breeding coloration, establish territories, and build shallow, circular nests. Nests may be solitary or colonial and males aggressively defend their nest, court females, and guard eggs and young.  Closely related species have a tendency to hybridize, complicating the identification.  Because of the high fecundity and parental guarding behavior, many young sunfish are produced and become prey for numerous sport fish and other aquatic predators, such as water snakes Nerodia, snapping turtles Chelydra serpentina, and hellbenders Cryptobranchus alleganiensis
Male sunfish guarding a circular, depression nest.  Photo by Alan Creech.  Creative Commons
The male nest construction and guarding and courting behaviors are well studied and all species of Lepomis demonstrate similarities in breeding.  The breeding male excavates a circular depression and defends the territory against all intruders.  This is a great time to get up close and personal with a male sunfish because they are so reluctant to flee.  See this photo of a beautiful male sunfish made possible because it was defending a nest.  During nest defense, the male sunfish displays to nearby or approaching males and females with a behavioral repertoire that consists of  nest hovering, dashes to the water surface and back to the nest, nest sweeping with caudal fin, fin spreading, mouth gapes, jaw snaps, lateral displays, substrate biting, and opercular spreads.  Rim circling behaviors where the male rapidly swims around the edge of the nest with fins erect are intended to attract a female. Opercular flaring is directed at females and apparently signals to the female the species, condition, and quality of the breeding male.  Males also use sounds to court mates.  If the female follows, the male performs courtship circles, encircling the female and leading her to the nest. The size of the male earflap is a key determinant of dominance in a hierarchy. 

Here are the eight species of sunfishes of Virginia.  

Redbreast Sunfish Lepomis auritus is native to the Atlantic slope drainages of Virginia but is now well established in all Virginia waters, except some acidic swampy drainages.  This sunfish has a moderate size mouth  with the upper jaw extending to the anterior edge of the eye.  Body is olive on the back and sides with yellow orange spots on the side and an orange breast.  Iridescent blue wavy lines radiate from the mouth across the snout and onto the cheek and opercle.   The ear flap is narrow and elongate, dark to the posterior margin. 
Redbreast Sunfish Lepomis auritus. Photo by Noel Burkhead.  Source
Green Sunfish Lepomis cyanellus is a very common and spunky sunfish that may occur in streams, rivers, ponds, and shallow weedy margins of lakes. The body shape is not as deep and the mouth is large. The coloration is blue green on back and sides with reflections of yellow and emerald.  The cheeks have distinctive blue wavy streaks.  The ear flap is black with white or yellow orange margins and is not elongated or flexible as in some other sunfish.  Black blotches are usually present near the base of soft dorsal and anal fins.  The pectoral fin is rounded and, when bent forward, will not extend beyond the front of the eye.  The fringe of white, yellow and/or orange along the fins develops in breeding males.   
Green Sunfish Lepomis cyanellus.  Photo by Nate Tessler
Pumpkinseed Lepomis gibbosus seem to prefer vegetated streams, ponds, and reservoirs.  Pumpkinseeds have wavy blue lines on the cheek and opercle.  The opercular flap is short and stiff with a black center, bordered by a semicircular spot on the posterior edge.  This spot may be white, pale yellow, or red.  The pectoral fin is long, and sharply pointed. When bent forward, the pectoral fin will reach beyond the front of the eye.  Pumpkinseed have specialized molariform teeth in their throat, used for crushing snail shells.  
Pumpkinseed Lepomis gibbosus.  Photo by Olaf Nelson.  Creative Commons
Warmouth Lepomis gulosus occur in vegetated lakes, ponds, swamps, reservoirs, and sluggish habitats in streams.  Warmouth has a large, terminal oblique mouth with lower jaw projecting slightly past the upper jaw.  Three to five dark red bands radiate from the snout.  The opercular flap is short and stiff, and black with paler often red-tinged border.  The coloration is olive brown with dark brown mottling on back and side and dark spots and bands on fins.  The pectoral fin is short and round, usually not reaching the eye when laid forward.  Breeding males (pictured below) are boldly patterned with a red orange spot at the base of the second dorsal fin and black pelvic fins.  
Warmouth Lepomis gulosus.   Photo by Olaf Nelson.  Creative Commons
Bluegill Sunfish Lepomis macrochirus occupy all types of lacustrine and fluvial habitats.  Bluegill have a small mouth.   They have a large black spot at posterior end of soft dorsal fin.   Opercular flap is moderate or long and flexible with black margins. Coloration is blue with dark chain-like bars along the side, which may be absent.  Adults will have two blue streaks from the chin to the edge of the gill cover.   Pectoral fin is long and pointed.     
Bluegill from Lake Lanier, Georgia.  Creative Commons
Hybrid Bream -- The hybrid between the Bluegill Sunfish and the Green Sunfish is commonly produced and marketed for stocking in farm ponds.  The F1 has desirable traits such as enhanced growth and reduced fertility.  The photo below is a hybrid that has blue cheek lines of the Green Sunfish and chain-like bars of the Bluegill. 
Hybrid Bream.  Photo by MSU Extension Service/Wes Neal
Dollar Sunfish Lepomis marginatus occur only below the fall line and inhabit swamp-like habitats in low gradient streams and beaver ponds.  They are the smallest Lepomis in Virginia, and max out at only 4 inches.  The mouth is small and there are wavy blue lines on cheek and opercle.  The opercular flap is long, flexible, black in the center and edged with lighter margins.  Coloration is dark red on back and bright orange on the belly with many blue spots on the side.    
Dollar Sunfish Lepomis marginatus  Photo by Derek Wheaton
Longear Sunfish Lepomis megalotis  inhabits pools of headwaters, creeks, and small to medium sized rivers.  Longear Sunfish have distinctive wavy blue lines on snout, cheek, and opercle.  The opercular flap is long and flexible with a black center and shite edges of equal with.  the pectoral fin is short and rounded, not reaching the eye when laid forward.   Adults are dark red above, bright orange below, and marbled and spotted with blue on the side.  Longear Sunfish vigorously attach a variety of baits and is frequently caught with spin and fly fishing.  
Longear Sunfish  Lepomis megalotis.  Photo by Brett Albanese, Georgia DNR
Redear Sunfish Lepomis microlophus inhabits ponds lakes and reservoirs and sluggish pools and backwaters of rivers. Redear Sunfish resemble Bluegill. They do not have wavy blue lines on the head.  The opercular flap is short, with black center  and bordered above and below in white margins and posteriorly with a prominent red or orange crescent.  Coloration is light gold green above with many dark connected spots on the side.  Pectoral fin is long and pointed.     It is widely stocked for sport fishing and eats snails and small bivalves, earning it the name "shellcracker."  Anglers catch Redear Sunfish with worms and other natural baits fished near the bottom.  
Redear Sunfish  Lepomis microlophus.  Photo by Kentucky Dept. of Fish & Wildlife Resources.
The fascinating sunfishes Lepomis spp. are North American treasures.   They are easy to catch, fun to watch, good to eat, and provide many opportunities for education and scientific study.   In addition to the Lepomis spp., other centrarchid fishes include the include Mud Sunfish (Acantharchus pomotis), Flier (Centrarchus macropterus), two rock basses (Ambloplites), three banded sunfishes (Enneacanthus), two crappies (Pomoxis),  and three black basses (Micropterus).    

Catching sunfish makes young ones happy.  Photo by Joseph Bartmann.  Creative Commons


Warren Jr., M.L., 2009.  Centrarchid identification and natural history.  Pages 375-533 in S.J. Cooke and D.P. Philipp, editors. Centrarchid fishes: Diversity, Biology, and Conservation.  Blackwell Publishing, Ltd., United Kingdom.