Just in time for the Flag Day/Father’s Day weekend, the Jordanella floridae we raise here at susquehannawildlife.net headquarters to help control hair algae in our planted aquaria are beginning to spawn.
A male Jordanella floridae displaying for a prospective female mate. A receptive female will nip the fins of a courting male prompting him to chase her.
In the wild, Jordanella floridae inhabits a variety of vegetated tropical wetlands and backwaters on the Florida peninsula. The species was first described there on Lake Munroe in 1879 by George Brown Goode and Tarleton Hoffman Bean, both of whom spent time working for the Smithsonian National Museum and the United States Fish Commission, the latter a forerunner of the U. S. Fish and Wildlife Service. Goode and Bean collaborated frequently, chronicling the occurrence of freshwater species like J. floridae as well as marine ichthyofauna. In 1896, the duo published Oceanic Ichthyology, an extensive study of pelagic and deep-sea fishes. Each experienced a prestigious career and has had numerous fish species named after him.
Nineteenth-century ichthyologist Tarleton Hoffman Bean (1846-1916) was born along the shores of the Susquehanna below Conewago Falls in Bainbridge, Lancaster County, Pennsylvania. He became a renowned expert on methods of fish culture. (Public Domain image)To the female, the breeding colors of the dominant male Jordanella floridae are irresistible. To us, the star-spangled banner pattern of this native killifish (more specifically a pupfish) justifies the species’ oft-used common name: American Flagfish.After being chased by the male, the female American Flagfish turns pale in color, indicating to the male that she’s ready to mate. The pair then face each other and begin dancing around the nest site which has been prepared by the male. The dance often consists of the female maneuvering so as not to again face in the direction of her partner..To get into spawning position alongside his mate, the male flagfish must commence a series of rolling turns.Once the male is successful and the female is receptive, spawning quickly ensues and the pair swims sideways in a tight circle around the center of the nest site……as the eggs are deposited and fertilized.Female American Flagfish lay fewer than two dozens eggs, so the male must diligently guard the nest from potential outside threats to his progeny including snails, dragonfly nymphs, and other fishes. Periodically, he’ll use his fins to fan a current across the eggs to clear them of debris and assure an exchange of fresh water through the nest.For the male American Flagfish, obsessive patrol of the nest site and care of the eggs continues day and night. The American Flagfish, a dandy that dresses for his role as an All-American Dad.
There are two Conewago Creek systems in the Lower Susquehanna River Watershed. One drains the Gettysburg Basin west of the river, mostly in Adams and York Counties, then flows into the Susquehanna at the base of Conewago Falls. The other drains the Gettysburg Basin east of the river, flowing through Triassic redbeds of the Gettysburg Formation and York Haven Diabase before entering Conewago Falls near the south tip of Three Mile Island. Both Conewago Creeks flow through suburbia, farm, and forest. Both have their capacity to support aquatic life impaired and diminished by nutrient and sediment pollution.
This week, some of the many partners engaged in a long-term collaboration to restore the east shore’s Conewago Creek met to have a look at one of the prime indicators of overall stream habitat health—the fishes. Kristen Kyler of the Lower Susquehanna Initiative organized the effort. Portable backpack-mounted electrofishing units and nets were used by crews to capture, identify, and count the native and non-native fishes at sampling locations which have remained constant since prior to the numerous stream improvement projects which began more than ten years ago. Some of the present-day sample sites were first used following Hurricane Agnes in 1972 by Stambaugh and Denoncourt and pre-date any implementation of sediment and nutrient mitigation practices like cover crops, no-till farming, field terracing, stormwater control, nutrient management, wetland restoration, streambank fencing, renewed forested stream buffers, or modernized wastewater treatment plants. By comparing more recent surveys with this baseline data, it may be possible to discern trends in fish populations resulting not only from conservation practices, but from many other variables which may impact the Conewago Creek Warmwater Stream ecosystem in Dauphin, Lancaster, and Lebanon Counties.
So here they are. Enjoy these shocking fish photos.
Matt Kofroth, Watershed Specialist with the Lancaster County Conservation District, operates the electrofishing wand in Conewago Creek while his team members prepare to net and collect momentarily-stunned fish. Three other electrofishing units operated by staff from the Susquehanna River Basin Commission and aided by teams of netters were in action at other sample locations along the Conewago on this day.Really big fish, such as this Common Carp (Cyprinus carpio), were identified, counted, and immediately returned to the water downstream of the advancing electrofishing team. Other fish, such as the Swallowtail Shiner, Redbreast Sunfish (Lepomis auritus), Fallfish, and suckers seen here, were placed in a sorting tank.Fallfish (Semotilus corporalis) are very active and require plenty of dissolved oxygen in the water to survive. Fallfish, Rainbow Trout (Oncorhynchus mykiss), and Smallmouth Bass (Micropterus dolomieu) were quickly identified and removed from the sorting tank for release back into the stream. Other larger, but less active fish, including suckers, quickly followed.Small fish like minnows were removed from the sorting tank for a closer look in a hand-held viewing tank. This Fathead Minnow (Pimephales promelas) was identified, added to the tally sheet, and released back into the Conewago. The Fathead Minnow is not native to the Susquehanna drainage. It is the minnow most frequently sold as bait by vendors.A breeding condition male Bluntnose Minnow (Pimephales notatus).The Cutlips Minnow (Exoglossum maxillingua) is a resident of clear rocky streams. Of the more than 30 species collected during the day, two native species which are classified as intolerant of persisting stream impairment were found: Cutlips Minnow and Swallowtail Shiner.The Central Stoneroller (Campostoma anomalum) is a benthic feeder in creeks over gravel and sand.The Eastern Blacknose Dace (Rhinichthys atratulus) is found in clear water over pebble and stone substrate.The Longnose Dace (Rhinichthys cataractae) is another species of pebbly rocky streams.A juvenile Golden Shiner (Notemigonus crysoleucas). Adults lack the side stripe and grow to the size of a sunfish.A Swallowtail Shiner (Notropis procne) and a very young White Sucker (Catostomus commersonii) in the upper left of the tank.A probable Spotfin Shiner (Cyprinella spiloptera).A breeding male Cyprinella shiner, probably a Spotfin Shiner. Show-off!The Margined Madtom (Noturus insignis) is a small native catfish of pebbly streams.The Banded Killifish (Fundulus diaphanus) is adept at feeding upon insects, including mosquitos.A young Rock Bass (Ambloplites rupestris). This species was introduced to the Susquehanna and its tributaries.The Greenside Darter (Etheostoma blennioides) is not native to the Susquehanna basin. The species colonized the Conewago Creek (east) from introduced local populations within the last five years.The Tessellated Darter (Etheostoma olmstedi) is a native inhabitant of the Susquehanna and its tributaries.The stars of the day were the American Eels (Anguilla rostrata).After collection, each eel was measured and weighed using a scale and dry bucket. This specimen checked in at 20 inches and one pound before being released.Prior to the construction of large dams, American Eels were plentiful in the Susquehanna and its tributaries, including the Conewago. They’ve since been rarities for more than half a century. Now they’re getting a lift.American Eels serve as an intermediate host for the microscopic parasitic glochidia (larvae) of the Eastern Elliptio (Elliptio complanata), a declining native freshwater mussel of the Lower Susquehanna River Watershed. While feeding on their host (usually in its gills), the glochidia cause little injury and soon drop off to continue growth, often having assured distribution of their species by accepting the free ride. Freshwater mussels are filter feeders and improve water quality. They grow slowly and can live for decades.American Eels are a catadromous species, starting life as tiny glass eels in the saltwater of the Atlantic Ocean, then migrating to tidal brackish marshes and streams (males) or freshwater streams (females) to mature. This 20-incher probably attempted to ascend the Susquehanna as an elver in 2016 or 2017. After hitching a ride with some friendly folks, she bypassed the three largest dams on the lower Susquehanna (Conowingo, Holtwood, and Safe Harbor) and arrived in the Conewago where she may remain and grow for ten years or more. To spawn, a perilous and terminally fatal journey to the Sargasso Sea awaits her. (You may better know the area of the Sargasso Sea as The Bermuda Triangle…a perilous place to travel indeed!)
SOURCES
Normandeau Associates, Inc. and Gomez and Sullivan. 2018. Muddy Run Pumped Storage Project Conowingo Eel Collection Facility FERC Project 2355. Prepared for Exelon.
Stambaugh, Jr., John W., and Robert P. Denoncourt. 1974. A Preliminary Report on the Conewago Creek Faunal Survey, Lancaster County, Pennsylvania. Proceedings of the Pennsylvania Academy of Sciences. 48: 55-60.
