Emerald Shiner: Caring for Notropis atherinoides
- aquaterraobsession
- Sep 9
- 11 min read
Comprehensive Biotope and Aquarium Care Sheet
:
This care sheet is a definitive guide for both biotope-focused aquarium hobbyists and ecological educators. By comprehensively detailing care, natural associations, and environmental considerations for the Emerald Shiner, this sheet ensures both healthy fish and authentic display.
Table of Contents
Introduction
The Emerald Shiner (Notropis atherinoides) is an iridescent, slender-bodied minnow that is a vital component of North American aquatic ecosystems, particularly within the Mississippi Basin and Great Lakes regions. Renowned both as a forage species for larger fish and as a hardy, silvery bait minnow, the Emerald Shiner offers a unique opportunity for aquarists to observe natural schooling behavior and contribute to native species awareness. Providing optimal care for this species requires understanding its taxonomy, biotope, behavior, and environmental needs, all of which are deeply interconnected.
Summary Table
Parameter | Details |
Scientific Name | Notropis atherinoides |
Common Names | Emerald shiner, Buckery shiner, Lake shiner, River emerald shiner |
Family | Leuciscidae (Minnows and Shiners) |
Native Range | North America: Southern Canada to Gulf of Mexico |
Maximum Length | 89–127 mm (3.5–5.0 in), up to 13 cm possible |
Lifespan | 4–5 years (females tend to be longer lived) |
Water Temperature | 20–25°C (68–77°F) |
Spawning Temperature | 20.1–23.2°C (68.2–73.8°F) |
pH Range | 6.5–8.0 |
Water Hardness | 5–15 dGH (moderate; variable tolerance) |
Oxygen Tolerance | Tolerant of low oxygen levels |
Habitat Type | Large rivers, lakes, and reservoirs; sand/gravel substrate |
Social Behavior | Schooling, midwater-to-surface dwelling |
Diet (Wild) | Zooplankton, protozoans, diatoms, insects, algae, detritus |
Diet (Captivity) | Planktonic foods, insect flakes, plant matter, frozen/live foods |
Breeding | Oviparous, pelagic spawner, temperature- and season-dependent |
Compatibility | Schooling, peaceful, suitable for native-themed or community tanks |
IUCN Red List | Least Concern (LC) |
Taxonomy and Identification
The Emerald Shiner is a member of the Leuciscidae family—the "true minnows," daces, and shiners. It is classified under:
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii (ray-finned fishes)
Order: Cypriniformes
Family: Leuciscidae
Genus: Notropis
Species: Notropis atherinoides
Binomial: Notropis atherinoides Rafinesque, 1818
Synonyms historically include Minnilus dinemus, Alburnus nitidus, Alburnellus jaculus, among others. The genus Notropis is taxonomically complex, with N. atherinoides grouping closely with N. hudsonius, N. percobromus (now synonymized), and others.
Key physical identifiers:
Coloration: Iridescent silvery green sides, distinct silver mid-lateral band, emerald-greenish or straw back, silvery white belly.
Morphology: Slender, somewhat compressed body; large terminal mouth (no barbels); transparent dorsal fin with 8 rays; 9–12 anal rays; 35–43 lateral line scales; 14–16 pectoral fin rays; blunt snout; clear or white fins.
Sexual Dimorphism: Females generally larger and longer-lived; males display small pectoral fin tubercles in breeding condition but no dramatic nuptial coloration.
These characteristics make Emerald Shiners distinguishable from other shiner and minnow species, though care is warranted as ranges and habitats may overlap with visually similar Notropis species (e.g., Spottail, Plains, or Steelcolor shiners).
Native Range and Biotope Characteristics
Emerald Shiners are native to a vast swath of North America. Their range includes:
St. Lawrence drainage (Quebec), Hudson River (NY), to Mackenzie River (Northwest Territories)
South through the Great Lakes and Mississippi River basins to the Gulf of Mexico
Gulf Slope drainages from Mobile Bay (Alabama) to Galveston Bay (Texas).
They are especially prevalent and often the most abundant small fish in the Mississippi River and Great Lakes, where they are an ecological keystone species
Habitats:
Large, open rivers and lakes with clear to moderately turbid water.
Move freely between main channels, secondary channels, oxbow lakes, and river margins.
Prefer sand or gravel substrates, though can also be found near clay or silt beds.
Juveniles are especially associated with natural vegetated marshes.
Submerged tree roots and overhanging willows/cottonwoods are common in their microhabitats, especially in the Lower Mississippi and its tributaries.
Biotope Summary Table
Feature | Description |
Dominant Waterbody | Mississippi, Missouri, Ohio, Great Lakes, large northern rivers |
Preferred Microhabitat | Open midwater zones, sand/gravel bottom, submerged wood/roots |
Vegetation Presence | Submerged grasses, algae, variable macrophyte cover |
Currents | Moderate to strong current typical; can inhabit slower waters |
Cohabitants | High diversity; especially with sunfish, perch, catfish, other shiners; native mussels and turtles also found |
The temperature in native biotopes can fluctuate from near freezing to above summer highs of 25–31°C (77–88°F), but optimal long-term habitat is close to 20–25°C.
Water Parameters: Wild vs. Aquarium
Wild parameters:
Temperature: 20–25°C (68–77°F), spawning at 20.1–23.2°C (68.2–73.8°F)
Dissolved Oxygen: Tolerant of low levels (wild range: 5.5–11 mg/L, or even lower seasonally over silt beds)
pH: 6.5–8.0 (variable—rivers can range from neutral to moderately hard)
Substrate: Sand, gravel, clay, and occasional silt or mud
Turbidity: Moderate tolerance, though dense populations prefer clearer water
Comparison Table: Wild vs. Aquarium
Parameter | Wild Range / Recommendation | Recommended Aquarium Value |
Temperature | 20–25°C (up to 31°C) | 20–25°C (68–77°F) |
pH | 6.5–8.0 | 7.0–7.8 |
Hardness (dGH) | 5–15 (variable) | 6–12 |
Dissolved Oxygen | Tolerant to low levels | ≥7.0 mg/L (well-aerated) |
Substrate | Sand/gravel (with silt/clay patches) | Fine sand or small gravel |
Current | Moderate to strong | Moderate flow/filtration |
It is important to avoid temperature shocks—acclimate fish slowly to the tank's conditions to ensure survival and long-term health.
Aquarium Tank Setup and Equipment Recommendations
Tank Size: Emerald Shiners are active, schooling fish that should be kept in groups of at least 6, but ideally 12 or more. For a small school, a 30-gallon (113-liter) tank is the absolute minimum; 55 gallons or larger is preferred for more authentic movement and reduced stress.
Substrate: Fine gravel or sand mimics native conditions. Mixes of sand/gravel and some rounded river stones replicate spawning habitats. Clay patches or leaf litter may be used in larger systems to reproduce riverbank zones.
Decor and Aquascaping:
Open swimming spaces are crucial for schooling and natural behavior.
Use driftwood, root tangles, or submerged branches to simulate riversides and offer retreats.
Submerged and emergent plants enhance authenticity; see plant list below.
Filtration and Water Flow:
Use canister or large hang-on-back filters; consider powerheads to create moderate current and increase oxygenation.
Sponge prefilters are recommended to protect eggs and fry during spawning attempts.
Aeration: An air bubbler or increased surface agitation (via powerhead or filter output) maintains oxygen and mimics flowing water.
Lighting: Moderate lighting is adequate—these fish frequent midwater and surface layers in the wild, often in well-lit zones near the water’s surface.
Other Recommendations:
Secure lids: Emerald Shiners are excellent jumpers, particularly when stressed or startled.
Partial surface cover: Floating plants or driftwood can help reduce skittishness.
Key Equipment List:
Appropriately sized glass or acrylic aquarium (≥ 30 gal/113L preferred)
External power filter (canister or large HOB)
Additional air pump and stone (especially for warmer tanks)
Substrate: sand/fine gravel mix
Driftwood/root structures and smooth rocks
Aquatically suitable plants (native, robust, and/or cold-tolerant)
Reliable heater (if room temperature drops below 20°C/68°F)
Moderate LED lighting
Diet in Wild and Captivity
Diet in the Wild
Emerald Shiners are mainly planktivorous, with dietary variations through development:
Zooplankton: Daphnia, copepods, cladocerans, rotifers
Protozoans and Diatoms: Abundant among juveniles and yearlings
Aquatic and Terrestrial Insects: Midges, flies, small beetles, mayflies; insects captured at the surface are a small but important seasonal part of their diet
Algae and Aquatic Plants: Eaten especially in spring; blue-green and green algae noted
Detritus and Small Crustaceans: Amphipods, some oligochaetes
Wild foraging is often sight-based and aligned with planktonic/microbial blooms—fish ascend to the surface at dusk and descend at dawn in response to plankton distribution.
Diet in Captivity
A varied, high-protein and plant-including diet helps to maximize health:
Flake Foods: High-quality community and insect-based flakes
Small Pellets: Sinking micro-pellets or crumbled carnivore pellets mimic zooplankton
Frozen Foods: Daphnia, brine shrimp, bloodworms, cyclops—all heavily accepted
Live Foods: If possible, small daphnia, baby brine shrimp, microworms, blackworms (ensure cultured clean to avoid pathogens)
Vegetable Matter: Spirulina flakes or blanched spinach/zucchini as a supplement
Feeding regimen: Small, frequent feedings (2–3 times daily) simulate their wild, constant-grazing habits.
Behavior and Social Structure
Schooling Behavior: Emerald Shiners are highly social, forming large or moderate schools of dozens to thousands in natural waters. Schooling offers significant anti-predator advantages (confusion effect, reduced individual risk) and enhances foraging efficiency.
Vertical Movement: In lakes and slow rivers, these fish migrate vertically with plankton, ascending to the surface at dusk and retreating to deeper, dimmer waters at dawn.
Diurnal Activity: Emerald Shiners are most active during daylight or crepuscular periods. In aquaria, movement is highest when the tank is well-lit.
Spawning Schooling: During the breeding season, emergent and complex synchronized mating dances occur, typically involving multiple males to each female.
Response to Threats: Studies show that shiners will increase school density and shift position in response to simulated predation, but return to original patterns rapidly when stress is removed, highlighting their resilience and adaptability to change with proper conditions.
Compatibility with Other Species
Emerald Shiners are peaceful, non-territorial, and not prone to aggression. They do best with:
Other peaceful, similarly sized schooling or shoaling North American fishes
Some small to medium sunfish, native darters (if not aggressive), white or yellow perch, non-predatory cyprinids, and some species of catfish
They will be eaten by any large predatory fish (bass, walleye, pike, big catfish)—do not mix with predator species if you wish to maintain a stable school in the tank
Should not be kept with overly aggressive or nippy tank mates—aggressive barbs, large cichlids, or large predatory catfish are best avoided
Compatibility Table
Species Type | Compatibility with Emerald Shiners |
Similar-sized shiners | Excellent |
Small sunfish | Good (monitor for fin nipping) |
Darters and sculpins | Good to Moderate (species dependent) |
Large cichlids/predators | Not recommended |
Community tetras/rasboras | Good; ensure similar temp needs |
Cohabitant Fish Species in Native Habitat
Below is a representative table with fish species commonly sharing the Emerald Shiner's biotope in the Upper Mississippi, lower Great Lakes, and related river systems (sources: empirical fish surveys, Iowa DNR, USGS, [36†source], [38†source], [0†source]):
Common Name | Scientific Name | Family | Notes |
Spottail Shiner | Notropis hudsonius | Leuciscidae | Very close relative, identical biotope |
Plains Shiner | Notropis percobromus* | Leuciscidae | Now incorporated as Emerald Shiner |
Fathead Minnow | Pimephales promelas | Leuciscidae | Wide-ranging, shares current/turbidity prefs |
Bluntnose Minnow | Pimephales notatus | Leuciscidae | Common, especially in tributary streams |
Yellow Perch | Perca flavescens | Percidae | Abundant predator and competitor |
Bluegill/Sunfish | Lepomis macrochirus, L. spp. | Centrarchidae | Common throughout lakes and rivers |
Channel Catfish | Ictalurus punctatus | Ictaluridae | Common large river cohabitant |
Freshwater Drum | Aplodinotus grunniens | Sciaenidae | Abundant benthic predator |
Walleye | Sander vitreus | Percidae | Primary predator on shiners |
Golden Shiner | Notemigonus crysoleucas | Leuciscidae | Overlapping open water, larger, more robust |
Blacknose Dace | Rhinichthys atratulus | Leuciscidae | Smaller, but seen in same smaller streams |
*Note: Plains Shiner now subsumed under Emerald Shiner in many sources due to range and genetic evidence.
These fish together make up a significant portion of community structure in open-water, moderate-flow river and lake systems in the Midwest/northern United States and southern Canada.
Aquatic Plant Species in Native Biotope
While Emerald Shiners are most associated with open water and sparsely vegetated sand or gravel bottoms, aquatic plants (macrophytes) feature significantly in river margins, backwaters, and shallow areas. Plants play an indirect but significant role by fostering invertebrate production and providing shelter for juvenile fish—including Emerald Shiner fry.
Frequently encountered plant types in their North American native habitats:
Plant Type | Genus/Species | Usage/Ecology |
Submersed Ribbon Plant | Vallisneria americana ("Water Celery") | Provides shelter and egg substrate |
Pondweed | Potamogeton spp. | Food for inverts, cover for fry |
Watermilfoil | Myriophyllum spp. | Structure for inverts, fry refuge |
Coontail | Ceratophyllum demersum | Common in slow rivers, fry shelter |
Elodea | Elodea canadensis | Abundant in cool lakes |
Duckweed | Lemna spp. | Marginal food, cover for fry |
American Lotus | Nelumbo lutea | Important in some river oxbows |
Arrowhead | Sagittaria spp. | Emergent; margins of lakes/rivers |
Cattails | Typha spp. | Emergent; nursery for inverts/fry |
In large rivers like the Mississippi, several distinct plant community types exist, with Diverse (macrophyte) and Water Celery communities being especially prominent. These plant zones support greater aquatic insect and invertebrate diversity—key Emerald Shiner diet items.
Aquatic Invertebrate Species in Native Biotope
Emerald Shiners feed on, and are surrounded by, a rich invertebrate fauna—benthic and planktonic—in native river and lake environments.
Key invertebrate taxa in their diet and habitat:
Invertebrate Group | Example Genera/Species | Notes |
Cladocera (Water Fleas) | Daphnia spp., Bosmina spp. | Primary zooplankton food |
Copepods | Cyclops, Diaptomus spp. | Ubiquitous plankton grazers |
Rotifers | Brachionus, Keratella spp. | Important microplankton |
Chironomidae (Midges) | Chironomus, Parachironomus, Polypedilum | Midge larvae abundant in benthos/plankton |
Mayfly Nymphs | Baetis, Hexagenia, Pentagenia | Major in both lake/midstream zones |
Caddisfly Larvae | Hydropsyche, Potamyia | Cling to rocks, drift at night |
Oligochaetes (Tubificids) | Limnodrilus spp. | Deposit feeders in silt/mud |
Mollusks | Corbicula fluminea, Sphaerium transversum | Small clams (food and habitat role) |
Amphipods (Scuds) | Gammarus spp. | Benthic prey |
Leptophlebia/other Mayfly | Leptophlebia sp., Tortopus incertus | Spawning in backwaters, important as food |
Chaoborid larvae | Chaoborus punctipennis | Phantom midge, transparent planktonic larva |
Leeches | Hirudinea | Not a primary food but occasionally consumed |
This diversity provides both direct nourishment for shiners and structure for benthic and planktonic food webs. Healthy, invertebrate-rich biotopes are critical for the thriving of Emerald Shiner populations.
Breeding and Reproduction
Spawning Behavior: Emerald Shiners are oviparous, pelagic spawners. Spawning occurs from mid-May to mid-August (external conditions determine peak periods), typically at night, 1–2 feet below the surface, in open water above gravel shoals or near large rocks. Courtship involves males pursuing larger females, with pairs circling and intertwining fins. Upon spawning, eggs are release by the female and fertilized externally by one or more males.
Reproduction Parameter | Value/Details |
Spawning trigger | Temperature > 22.2°C (72°F) |
Spawning substrate | Open water above gravel/boulder / moving current |
Egg Type | Numerous, buoyant, low-pigment, adhesive |
Fecundity | 2000–9000 eggs per female (varies with size/age) |
Incubation period | 24–32 hours at optimal temperatures |
Juvenile growth | Fast; yearlings reach 50% adult size by first fall |
No parental care is given post-spawning. Eggs drift to the substrate, where survival is highest in clean, oxygenated, flowing water. Emergent larval Emerald Shiners feed primarily on protozoans and rotifers, moving up to small zooplankton as they grow.
Key for successful captive spawning:
Slight temperature increase and mimicry of riverine photoperiod triggers spawning
Increased current and addition of rounded spawning stones may encourage natural behavior
Eggs can be removed to hatching tank to minimize predation
Health, Common Diseases, and Prevention
Emerald Shiners are hardy and cold-tolerant, but several points optimize their health in aquaria:
Water Quality: Stable, well-oxygenated water with good filtration and regular partial water changes is critical.
Disease Risks: Wild-caught or bait shop Emerald Shiners may carry pathogens or parasites. Quarantine recommended for at least 3 weeks.
Stress: Overcrowding, poor diet, or abrupt temperature shifts may lead to stress and susceptibility to disease.
Common Issues: Ich (white spot), parasitic worms, bacterial infections. These can be minimized by regular observation, quarantine of new stock, and maintaining tank hygiene.
Preventative Practices: Balanced nutrition, routine tank cleaning, moderate stocking, and monitoring for sudden behavior shifts.
Summary Disease Table
Pathogen/Disorder | Preventive Practice | Treatment if Present |
Ich (white spot) | Quarantine new fish, temp control | Heat and medicate as required |
Anchor worms | Visual inspection, quarantine | Potassium permanganate, manual removal |
Intestinal worms | Source control, regular feeding | Anti-parasitic medications |
Bacterial issues | Stable water quality | Antibiotics (vet consult) |
Velvet/vibriosis | Low stress, avoid temp swings | Copper-based meds, water stability |
For detailed disease identification, refer to recognized aquarium health guides.
Conservation Status and Environmental Threats
Emerald Shiner is classed as "Least Concern" by the IUCN Red List, with abundant and stable populations in native range. They remain key forage for birds (gulls, terns, cormorants, mergansers), predatory fish (walleye, pike, trout), and mammals.
Environmental Threats:
Habitat Change: Construction of dikes, dams, and reservoirs alters natural river hydrology, sometimes reducing suitable spawning and foraging habitat.
Water Quality Degradation: Pollution (chemical runoff, excess nutrients causing eutrophication) impairs plankton food webs, impacting shiner populations.
Invasive Species: Competition and predation from introduced fish (e.g., white perch, gizzard shad) may cause local abundance declines, per noted lake studies.
Bait Use/Overfishing: Intensive wild harvest as bait (especially in Great Lakes) can reduce local populations, though widespread range reduces risk of global depletion.
Current Management: No major conservation action required beyond habitat protection and continued monitoring of water quality and invasive species impacts.
Conclusion
The Emerald Shiner (Notropis atherinoides) epitomizes the beauty and ecological importance of North America's native fish fauna. Its care—whether in the classroom, public exhibit, or enthusiast's aquarium—demands attention to its open-water schooling needs, omnivorous feeding habits, and sensitivity to biotope authenticity. By closely emulating natural water parameters, providing ample swimming space, and choosing compatible tank mates (and biotope-appropriate plants and invertebrates), aquarists can maintain vibrant, healthy groups that display their instinctive schooling and feeding behaviors.
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