1. Aspects of Bowfin and Northern
Sunfish Biology and Ecology
Chapter 1
Population Characteristics of Bowfin (Amia
calva) from a Great Lakes Coastal Wetland,
with an Investigation of Captive Breeding
and Artificial Diet
Chapter 2
Status of the Last Wild Population of Northern
Sunfish (Lepomis peltastes) in New York State:
Changes in the Fish Community and
Hybridization with Bluegill (L. macrochirus) in
Tonawanda Creek, Erie County
2. Population Characteristics of Bowfin (Amia calva) from a Great
Lakes Coastal Wetland, with an Investigation of Captive
Breeding and Artificial Diet
• Maximum
– Length: 939 mm (37 in)
– Weight: 9.75 kg (21lb 8oz)
– Age: 30 yrs captivity;
13 in the wild
– One of the highest
recorded growth
rate of any fish
(10% BW/day from
20–200 g)
Introduction http://www.iquitfilmschool.com/adventures-with-bowfin-north-americas-underdogfish/
3. Population Characteristics of Bowfin (Amia calva) from a Great
Lakes Coastal Wetland, with an Investigation of Captive
Breeding and Artificial Diet
• Common throughout
most of the eastern
US
http://nas.er.usgs.gov/queries/factsheet.aspx?SpeciesID=305
Introduction: Range
4. Population Characteristics of Bowfin (Amia calva) from a Great
Lakes Coastal Wetland, with an Investigation of Captive
Breeding and Artificial Diet
• Only living member of Order: Amiiformes
– Triassic period
(~251 MYBP)
Introduction: Phylogeny
http://whozoo.org/fish/fishtaxa.htm
5. Population Characteristics of Bowfin (Amia calva) from a Great
Lakes Coastal Wetland, with an Investigation of Captive
Breeding and Artificial Diet
• Air-breathing
– highly vascularized swim
bladder
http://bio.sunyorange.edu/updated2/comparative_anatomy/anat.html1/R_LUNGS.htm
Introduction: Biology
6. Population Characteristics of Bowfin (Amia calva) from a Great
Lakes Coastal Wetland, with an Investigation of Captive
Breeding and Artificial Diet
• Sexually dimorphic year-round
Female
Male
Introduction: Biology
7. Population Characteristics of Bowfin (Amia calva) from a Great
Lakes Coastal Wetland, with an Investigation of Captive
Breeding and Artificial Diet
• Males build and guard nests
– Where water is ~0.5–1 m
– He chews away stalks of vegetation,
fans away muck, and creates a bowl with
fibrous roots for eggs to adhere
• Young stay in tight schools defended my male
until they reach ~100 mm
Introduction: Reproduction
8. Population Characteristics of Bowfin (Amia calva) from a Great
Lakes Coastal Wetland, with an Investigation of Captive
Breeding and Artificial Diet
http://www.dailykos.com/story/2014/4/6/1290055/-The-Daily-Bucket-Baby-Bowfin-and-Other-Adventures-at-the-Dock
Introduction: Reproduction
http://www.nanfa.org/fif/bowfin.shtml
9. Population Characteristics of Bowfin (Amia calva) from a Great
Lakes Coastal Wetland, with an Investigation of Captive
Breeding and Artificial Diet
• Commercial harvest for
bowfin roe (eggs) as a
black caviar alternative
has boomed
– Sturgeon caviar limited
due to overexploitation
– Industry is expanding into
Georgia and up Mississippi
– Could expand into
Great Lakes
Introduction: Commercial Harvest
10. Population Characteristics of Bowfin (Amia calva) from a Great
Lakes Coastal Wetland, with an Investigation of Captive
Breeding and Artificial Diet
Introduction: Commercial Harvest
https://www.markys.com/Caviar/american-bowfin-black-caviar-1-oz..html#op16206
11. Population Characteristics of Bowfin (Amia calva) from a Great
Lakes Coastal Wetland, with an Investigation of Captive
Breeding and Artificial Diet
• Like sturgeon, they are long-lived
• Therefore, highly susceptible to overharvest
• In light of new industry, four populations have
recently been described using a reliable aging
method
Introduction: Commercial Harvest
12. Population Characteristics of Bowfin (Amia calva) from a Great
Lakes Coastal Wetland, with an Investigation of Captive
Breeding and Artificial Diet
• To evaluate the potential impact of commercial
harvesting in the Great Lakes
– Objective 1: To describe age and growth from a Lake
Ontario population and compare to those recently
described
• To develop an in-captivity alternative to commercial
harvesting (i.e. aquaculture)
– Objective 2: To explore the ability of wild bowfin to
survive and reproduce in the laboratory, and
– Objective 3: To determine whether adult bowfin would
accept an artificial diet in place of live fish.
Goals and Objectives
13. • 55 bowfin: (51 from Braddock Bay)
• Of the 51: 26 female, 25 male
• 579 (±90) mm long, 1880 (±1018) g weight, 4.2 (±1.4) yrs old
Methods: Population Characteristics
14. • Data from aging used to determine growth
characteristics
– Bowfin do not display annuli on scales
– Otoliths are irregularly shaped
– The best hard structure to use is thin sections of the first pectoral fin ray
– Gular plate also acceptable, but not as reliable
Methods: Population Characteristics
15. • Data from aging used to determine growth
characteristics
– Bowfin do not display annuli on scales
– Otoliths are irregularly shaped
– The best hard structure to use is thin sections of the first pectoral fin ray
– Gular plate also acceptable, but not as reliable
Methods: Population Characteristics
21. Results: Population Characteristics
Back-calculated length-at-age
0
100
200
300
400
500
600
700
800
900
1 2 3 4 5 6 7 8 9 10 11 12 13
Length(mm)
Age (yrs)
Lake Ontario
UMR Pool 11
UMR Pool 13
Mingo Swamp*
Lake Lindsay Grace
Barataria Estuary*
22. Conclusions: Population Characteristics
• This bowfin population from Lake Ontario grows slower than those
from lower latitudes
• This population resembles those from the Upper Mississippi River,
which the authors (Koch et al. 2009) warned were vulnerable to over
exploitation
• If the industry expands into the Great Lakes, more surveys with
larger sample sizes should be conducted to assess the populations’
Maximum Sustainable Yield, recruitment, age of maturity, etc.
23. Methods: Captive Breeding
Recall:
• Goal: To develop an in-captivity alternative to wild harvest
• Objective 2: To explore the ability of wild bowfin to survive and
reproduce in captivity, and
So I tested 2 aquaculture ponds...
24. Methods: Captive Breeding • 0.04 hectares (1/10th acre)
• 2 m depth
• Clay lined with ~10 cm organic muck
• 2 ♂ ; 3 ♀
25. Methods: Captive Breeding • 0.04 hectares (1/10th acre)
• 2 m depth
• Clay lined with ~10 cm organic muck
• 2 ♂ ; 3 ♀
26. Methods: Captive Breeding
...and 5 indoor tanks
Tank 1 (not shown):
152 cm x 76 cm x
121 cm; 1,415 L
(1 ♂ 2 ♀)
Tank 2 (left): 182
cm diameter x 90
cm; 2,341 L
(1 ♂ 2 ♀)
33. Results: Captive Breeding
There was no evidence of breeding in any tank or pond
Conclusions: Captive Breeding
• For commercial propagation, bowfin will require
hormone-induced breeding (i.e. Dabrowski 2012)
• Bowfin can “skip” spawning
— In wild, only 5/123 females bred in a season in
southeastern Louisiana (Davis 2006)
• Many issues with water quality led to mortality and most
likely triggered skipped spawning
• Ponds likely did not provide proper nesting area
— Steep banks, relatively small, too confined
34. Methods: Artificial Diet
Recall:
• Goal: To develop an in-captivity alternative to wild harvest
— Objective 3: To determine whether adult bowfin
would accept a prepared diet in place of live fish.
35. Methods: Artificial Diet
Recall:
• Goal: To develop an in-captivity alternative to wild harvest
— Objective 3: To determine whether adult bowfin
would accept a prepared diet in place of live fish.
I tested 2 artificial diets and a control diet of live prey
(3 treatments)
• Commercially available: Purina Mills® Aquamax
• Handmade: Ground Fish
• Live: goldfish, minnows, sunfish, tadpoles, and crayfish
36. Methods: Artificial Diet
12 adult bowfin: 1 female and 3 males each treatment
• 1 bowfin per tank
• 86-days from July 2nd to September 25th 2013
• Tracked consumption of each pellet and mass of feed
• Tanks: 121 cm x 60 cm x 30 cm; 226 L (4’ x 2’ x 1’; 58 gal)
— Flows, lights, and gravel substrate was provided equally
in each tank
37. Methods: Artificial Diet
12 adult bowfin: 1 female and 3 males each treatment
• 1 bowfin per tank
• 86-days from July 2nd to September 25th 2013
• Tracked consumption of each pellet and mass of feed
• Tanks: 121 cm x 60 cm x 30 cm; 226 L (4’ x 2’ x 1’; 58 gal)
— Flows, lights, and gravel substrate was provided equally
in each tank
41. Methods: Artificial Diet
I tracked each item of food and prey for consumption
• Aquamax and Ground Fish pellets were weighed and
tethered to a fishing string
• Prey items were weighed and assumed to have been eaten
when missing (screens were placed on all tank drains)
42. Results: Artificial Diet
All groups had an average loss in weight
-1000
-750
-500
-250
0
250
500
750
1000
-20%
-15%
-10%
-5%
0%
5%
10%
15%
20%
X3 Y4 Y6 Y9 X1 Y11 Y3 Y5 X2 Y1 Y10 Y7
DietConsumed(g)
PercentChangeinInitialWeight
Aquamax Ground Fish Control
But the Ground Fish diet lost significantly less weight
Kruskal-Wallace one-way ANOVA, F [2,9] = 9.19, P = 0.007
43. Results: Artificial Diet
All diets were consumed, with the Ground Fish
diet more preferred than the Aquamax
0
10
20
30
40
50
60
70
80
90
100
X3 Y4 Y6 Y9 X1 Y11 Y3 Y5 X2 Y1 Y10 Y7
PercentConsumption
Aquamax Ground Fish Control
44. Conclusions: Artificial Diet
The loss of weight is likely due to
• methods that only allowed one piece to be
consumed at time
• stressful conditions of captivity:
— tank size
— water conditions
— disturbances
45. Conclusions: Artificial Diet
The loss of weight is likely due to
• methods that only allowed one piece to be
consumed at time
• stressful conditions of captivity:
— tank size
— water conditions
— disturbances
More research is needed to develop ideal feeds
and feed rates for adult bowfin in captivity
(broodstock and grow-out)
46. Chapter 2 Status of the Last Wild Population of Northern
Sunfish (Lepomis peltastes) in New York State:
Changes in the Fish Community and Hybridization
with Bluegill (L. macrochirus) in Tonawanda
Creek, Erie County
47. Introduction
Status of the Last Wild Population of Northern Sunfish
(Lepomis peltastes) in New York State: Changes in the Fish
Community and Hybridization with Bluegill (L.
macrochirus) in Tonawanda Creek, Erie County
48. Introduction
Status of the Last Wild Population of Northern Sunfish
(Lepomis peltastes) in New York State: Changes in the Fish
Community and Hybridization with Bluegill (L.
macrochirus) in Tonawanda Creek, Erie County
longear sunfish
northern sunfish
49. Conservation Timeline
• Recovery program
initiated
– Assess status in Lower
Tonawanda Creek
– establish hatchery ponds
– Restock previous range and
new suitable sites
Captured 23
Northern Sunfish
2005; Scott Wells SUNY Brockport
2005; Doug Carlson NYSDEC
2005–2013; 19,000 fingerlings
50. Introduction: Recovery program
Status of the Last Wild Population of Northern Sunfish
(Lepomis peltastes) in New York State: Changes in the Fish
Community and Hybridization with Bluegill (L.
macrochirus) in Tonawanda Creek, Erie County
Erie (NYSB) Canal
= Moira River strain, = Tonawanda Creek strain, = Huron River strain
Lower Tonawanda Creek
51. Goals and Objectives
2013: To reassess New York’s last remaining wild population of northern
sunfish in lower Tonawanda Creek.
2014: The population could not be detected, attempt to detect the
species in other areas that had been stocked by NYSDEC.
52. Goals and Objectives
2013: To determine the status of New York’s last remaining wild
population of northern sunfish in lower Tonawanda Creek.
2014: The population could not be detected, detect the species in
other areas that had been stocked by NYSDEC.
— Species again was not detected, investigate the cause of the
northern sunfish’s decline in lower Tonawanda Creek.
— The objectives for achieving this goal were to:
• Determine if the fish community in lower Tonawanda Creek had
changed from 2005 to 2013, and
• Investigate whether hybridization of northern sunfish with other
Lepomis spp. had occurred in lower Tonawanda Creek.
53. Erie
Canal(NYBC)
W
atershed
2
Grand Island
Ontario,Canada
NiagaraRiver
Tonawanda Creek (TWC)
Watershed 1
Ransom Creek
Mud Creek
Murder Creek
A B C D E
G
H
Ledge Creek
I
A B C
D
E
Ellicott Creek (ELC)
Watershed 3
B
F
C D EA
F
Cayuga Creek (CYC)
Watershed 4
Buffalo River
Cazenovia
Creek
Buffalo
Creek
Little
Buffalo
CreekSlate Bottom Creek
Cayuga Creek
A
B
C D E
Buffalo
Niagara Falls
10 Kilometers
2005 L. peltastes detected
Huron River strain stocked
Tonawanda Creek strain stocked
54. Methods: Changes in Fish Community
Recall: To determine if the fish community in lower Tonawanda
Creek had changed from 2005 to 2013
• 46.12 hours of boat & backpack electroshocking power-on time
2013 & 2014
— 2014 data was presence/absence, so not used in calcs
— 2013 data from sites where northern sunfish were captured in
2005, using the same collection methods, were used to:
• Compare Catch Per Unit Effort (CPUE) of each species
• Compare Simpson’s Index of Diversity
• Create multivariate comparisons of the communities
• (18.58 hours of effort from 2013 used in these comparisons)
56. • 4 sampling dates
• All green sunfish > 24 mm marked
• Proportion of marked:unmarked indicates size of
population
Methods: Changes in Fish Community
Ministudy: Multiple mark-recapture assessment of
green sunfish (Schnabel method)
Results:
• Population estimated to be 8,606 green sunfish in
the 3.7 km stretch of lower Tonawanda Creek (95% CI:
6,297–12,116)
• Equates to 1.2 (95% CI: 0.9–1.7) green sunfish/meter
shoreline
57. Results: Changes in Fish Community
Simpson’s Index of Diversity; modified t-test (Brower & Zar 1984)
• Significantly lower in 2013 than 2005 (P = 0.004)
• Species richness also decreased
2005 2013
Simpson’s index of diversity (Ds) 0.790 0.715
# samples 12 40
Average richness (# spp./sample) 13.42 10.92
Cumulative richness (# spp.) 25 24
Simpson’s t value 3.05
Degrees of freedom (df) 47
Significance (P) 0.004
58. Results: Changes in Fish Community
Multivariate analyses using Bray-Curtis similarity matrix
(Primer 6)
• Significant difference in communities detected using ANOSIM
(R = 0.806, P = 0.001)
• Using SIMPER, differences attributed to...
60. Results: Changes in Fish Community
Multivariate analyses using Bray-Curtis similarity matrix
(Primer 6)
• Significant difference in communities detected using ANOSIM
(R = 0.806, P = 0.001)
• Using SIMPER, differences attributed to...
• Non-metric multidimensional scaling showed strong separation
between the two year’s samples
61.
62. Conclusions: Changes in Fish Community
The community in lower Tonawanda Creek has
changed significantly from when northern sunfish
were last detected
• Due to an overwhelming increase in non-native
green sunfish
• Other shifts:
— ↑ bluegill (competitors)
— ↑ round goby & white perch (invasives)
— ↑ pikes (predators)
— ↓ darters and logperch, redhorse suckers,
madtoms, and native cyprinids (indicator species)
63. Conclusions: Changes in Fish Community
• This community may not support northern sunfish
unless conditions change
• Future recovery efforts should identify new
waters suitable for northern sunfish containing no
green sunfish or round gobies
• Stocking and resampling should continue with a
more regimented schedule
65. Recall: To investigate whether hybridization of northern sunfish with other
Lepomis spp. had occurred in lower Tonawanda Creek.
• Sunfish species are known to hybridize in nature,
especially when one species becomes overbearingly
abundant and/or the habitat is degraded
• Sunfish nest in colonies, sometimes mixing with other
species when habitat is limited
• Alternative mating tactics are common
– cuckolding:
• small, non-nest building males
• dull coloration to mimic females
• sneak into an egg-bearing nest, fertilize, and run away
• Studies have shown hybridization to occur due to
cuckolding, particularly by bluegill males
Background: Hybridization study
66. • Several suspected hybrids were captured during
sampling
• A detailed key was developed using meristics,
morphometrics, and general descriptions from texts
• Suspected specimens did not fit the key
– These, along with pure-bred specimens of each species,
were:
• photographed
• frozen
• had DNA samples taken
• delivered to the NYS museum for further morphometric analysis
Methods: Hybridization study
67. Methods: Hybridization study
DNA analysis used microsatellite techniques to identify
mitochondrial and nuclear alleles as belonging to one of
the four sunfish species
68. Results: Hybridization study
27 specimens were indeed hybrids: (in father x mother order)
• 8 bluegill x northern
• 8 bluegill x green
• 8 bluegill x pumpkinseed
• 3 green x pumpkinseed
72. Conclusions: Hybridization study
• The remnant population of northern sunfish in lower
Tonawanda Creek was only detectable in 2013 & 2014
by genetic evidence left in hybrid specimens
• The proportion of northern hybrids is relatively higher
than other species’ crosses
— Supporting the theory that hybridization occurs when one
species is scarce and another highly dominant
• Remaining questions:
— Why only the four parental crosses?
— Why did bluegills hybridize with northern sunfish and not the
massively abundant green sunfish?
— Why were bluegills always the male parent?
• Remaining research (in progress):
— Use morphometric analysis, proofed by genetics, to help
researchers recognize and identify hybrid sunfish
73. Dedications: This thesis is dedicated to, first, my parents for their undying love, support,
and guidance: my mother who taught me to thirst for knowledge and my father who taught
me to explore natural phenomena. Second, I also dedicate this thesis to the love of my life,
Noelle Hatton, who not only helped with both chapter’s field and lab work, but has
unwaveringly stood by me through the writing process.
Acknowledgements: Dr. James Haynes for encouraging me to develop a thesis project that
captured my interests, for providing an immeasurable amount of support and guidance,
and for his patience. Dr. Jacques Rinchard for providing the facility and major components
of my bowfin project’s setup, as well as his support and guidance. Dr. Douglas Wilcox for
providing financial support and scientific input, as well as lending me much of the field gear
for capturing my bowfin.
Bowfin Research: Ant`hony Marsocci, Noelle Hatton, Corey Calby, Andie Graham, Erik Long,
Shane Barney, Colleen Kolb, Taylor Ouderkirk, Lauren Brewer, Miranda Papp, Matt Piche,
Jacob van Slooten, Joshua Perry, Evan Rea, Robert Cornish, Lier Yo, Kelly Owens, Amberlee
Todd, William Giese, Frank Lawrence. Expert opinions: Dr. Allyse Ferrera of Nicholls State
University, Thibodaux, Louisiana and Dr. Michael Quist of the University of Idaho, Moscow,
Idaho. Lowes, Brockport and Bruce Butcher of Sandy Creek Marina.
Northern Sunfish Research: NYSDEC Fish Biologists Douglas Carlson, for his mentorship of
me through this project and Scott Wells for his guidance. Funding from the Niagara River
Habitat Enhancement and Restoration Fund, with special thanks to Timothy DePriest,
NYSDEC HERF committe chair. Anthony Marsocci, Catherine Jirovec, Noelle Hatton, Andrea
Graham, Katherine Bailey, Coral Reina, Kelly Owens, Gregory Lawrence, Scott Buckingham,
Jeffery Maharan, Jonathan Bateman, Matthew Piche, Robert Cornish, Alyssa Vogel, Dena
VanCurran, Sage Hallenbeck, Mathew Pavalitis, Alexander Silva, James Hatton. Erie County
Department of Parks, Recreation, and Forestry.
