Fishing for Invasive Fishes - calendarmedia.blob.core ... · 1. Big River freshwater fish, deep holes and often found over hard bottom habitats 2. Can be abundant 3. Primarily eats

Fishing for Invasive Fishes

Joseph W. Love, Ph.D.Maryland Department of Natural Resources

What are they?

• Introduced pre-2000s– Native to Mississippi River– Introduced to Virginia rivers of

Chesapeake Bay watershed

• Ecology– Riverine or big water species– STAC Review/Bay Program– Preys on shad, other fish, and

invertebrates– Nocturnal– Can become very abundant

• Fishing– Spines, handling– Largest, oldest fish may harbor

biocontaminants

Blue CatfishFlathead Catfish

• Introduced in 2000s – Native to Asia (China, Vietnam)– Introduced to Maryland, D.C.

• Ecology– Preys on numerous North American aquatic

species, ducks (?) and mammals– Uses aquatic habitats occupied by freshwater

North American fishes– Wide habitat tolerances– High reproductive capacity– Thrives in high and low quality habitats

• Fishing– Relatively small fishery– Dehooking and Handling – slimy, toothy

Northern Snakehead

What makes them invasive?

Are these invasive?


Are these invasive?

• “Invasive” describes a species that, when introduced into an ecosystem aggressively establishes itself at the expense of native plants or animals (Department Website)

• Non-native species whose introductions causes, or is likely to cause, economic or environmental harm or harm to human, animal, or plant health (United States)


• Unlike carp and goldfish, the big three are top predators– Potentially impair many

levels within the food web– The resiliency of prey

populations to this additive predation pressure is not well-known



Angler Emanuel Tankersley caught this 19-pound, 5-ounce northern snakehead ( Channaargus ) last year, May 15, 2018 while fishing Potomac Creek in northern Virginia. Tankersley’s catch is now the new All-Tackle world record, certified by the International Game Fish Association. Photo courtesy of Emanuel Tankersley.

Caleb Newton, who lives in Spotsylvania County, Va., holds the 17-pound, 6-ounce northern snakehead fish he caught in June (2013). The International Game Fish Association has approved a world record for his catch of the invasive predator.


Angler Emanuel Tankersley caught this 19-pound, 5-ounce northern snakehead ( Channa argus ) last year, May 15, 2018 while fishing Potomac Creek in northern Virginia. Tankersley’s catch is now the new All-Tackle world record, certified by the International Game Fish Association. Photo courtesy of Emanuel Tankersley.

Caleb Newton, who lives in Spotsylvania County, Va., holds the 17-pound, 6-ounce northern snakehead fish he caught in June. The International Game Fish Association has approved a world record for his catch of the invasive predator.


Andrew D. Fox catches state record invasive fish, 19.90 pounds on May 24, 2018 from Mattawoman Creek near Indian Head.

Maryland Invasive Species State Records for Northern Snakehead



From Schmitt et al. 2017


From Schmitt et al. 2017


Magothy River


• Unlike bass, trout and other catfish, the big three have potential to significantly change the Chesapeake Bay ecosystem– Big populations, big impacts– Widespread distribution,

widespread impacts– Predation, disease

transmission




transmission

From Love and Newhard 2018




transmission


Flathead CatfishBlue CatfishNorthern Snakehead

How did they get here?

1970s

1970s

1985

Open Water Introductions

1995mid-1990s



1970s

1970s

1985


1995mid-1990s

2004

2002 2004


1995

2004

2002 2004


mid-1990s


1970s

1970s

1985


1995

2004

2002 2004

2010


mid-1990s 2006


1970s

1970s

1985



The Expansion2010 - 2019













1. Big River and estuarine fish2. Can become abundant in deep

water habitats3. Eats molluscs, crabs and fish4. Achieve large sizes, records near

and over 100 lbs

1. Big River freshwater fish, deep holes and often found over hard bottom habitats

2. Can be abundant3. Primarily eats fish4. Can achieve large sizes, up

to 100 lbs

1. Freshwater stream and marsh or lentic fish2. Can become very abundant3. Eats invertebrates, fish, amphibians; opportunistic4. Achieve large sizes, for stream fish – up to 20 lbs


What can we do?• Prevent new and

additional introductions– Education– Regulation

• Establish an early detection and rapid response mechanism– Education

• Control and slow spread– Encourage harvest

• Share what we know• Learn what we don’t• Through it all,

harvest

What can we do?

https://youtu.be/bCKR-rOiU80

What can we do?

Find new sources of money.Leverage resources, Make friends.

What can we do?

Do work.Build new infrastructure.

What can we do?

Do more work.Find more money.

• Encourage people to harvest– Minimize restrictions– Encourage and create social

fishing events– Create mechanisms to share

effective catching techniques• Sell inexpensive commercial

licenses– Snakehead bowfishing license– Invasive catfish trotline license

What can we do?

What can we do?

What can we do?

What can we do?

What can we do?

Northern Snakehead

Chesapeake Bay Blue Catfish

What can we do?

Chesapeake Bay Blue Catfish

What can we do?

What can we do?

What can we do?

Thank you.

Quantifiable Option Number of times suggested to

be implementedComments

No pre season catch and release (March and April) 2

A few of people asked that we not eliminate 'winter' catch and release. This option is March and April only and would not impact January and February.

May 1 Trophy Start 92 comments opposed impacting trophy season at all and several comments supported eliminating the trophy season completely.

July / August Closure > 21 days 3 A couple of additional comments supported shorter closures in July

Limit July / August hours to 10am No targeting rest of day 2

Eliminate the extra boat fish for charters 4 This is estimted to be a very small reduction in overall removals.

Shorten season in December 2 A couple of comments also opposed any days off at the end of the season

One fish bag limit 2 This was suggested for just part of the season

These regulatory ideas were provided to DNR staff over 9 meetings with striped bass anglers and charter boat captains around the Bay between June 17 and September 17, 2019. These options are quantifiable and can be combined to form the basis of a conservation equivalency proposal for ASMFC technical committee to review and for the management Board to consider in February.

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A B

Options Non Quantifiable. Unlikely to pass TC What would we need to know?

Create advisory days / educateBaseline number of advisory days. The fraction of people that would change their behavior based on the advisory. What the distribution of baseline behavior is.

Keep first 2 legal fish, then stop targeting

An estimate of the probability of capturing legal fish - e.g. how many fish would, on average be caught and disguarded before a legal fish is encountered. A baseline fraction of people who limit out and quick anyway vs. keep fishing.

Mandate minimum size of circle hooksA baseline average distribution of the size of circle hooks currently being used. Some study quantifying the relationship between circle hook size and mortality

Area closuresThe proportion of fish harvested in a given area. Fish distribution and driving factors such as water quality are not consistent from year to year, so this would be hard to pin a number to.

Require barbless hooks

The baseline fraction of people already fishing with barbless hooks. Studies that quantify the reduction of release mortality with use of barbless hooks for striped bass. Type of barbless hook probably matters as well as handling behavior and other gear characteristics.

Limit number of rods

A baseline of the average number of rods deployed per vessel and some idea of catch /rod /vessel and some measure of catch over time. If rods are limited to 3 and a vessel always fished 6 rods, how much catch can they make up by fishing longer? Vessels may limit out faster with more rods, lowering encounter time.

Limit planar boards to charter onlyA baseline average number of private boats using planar boards and the frequency of trips on which they are used. Also and more importantly, the number of lines associated with the planar boards.

Limit number of lines on planar boardsA baseline average number of lines on planar boards and the frequency of trips on which planar boards are used. Some charter boats may use upwards of 25 lines, and private boats may have a dozen or more.

Regulatory ideas provided to DNR staff over 9 meetings with striped bass anglers and charter boat captains around the Bay between June 17 and September 17, 2019. These options are non - quantifiable. We have included a short explanation of why we cannot place numbers on these ideas.

11

12

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15

A B

Options Non Quantifiable. Unlikely to pass TC What would we need to know?

Prohibit catch and release w/ baited hooks

The baseline fraction of people that fish with baited hooks. Then, what fraction of those people are soley catch and release fishing vs. 'keeper' fishing. How to separate catch and realeasing until you catch your 'keeper' fish from just catch and release fishing.

No Upper Bay catch and release season Finer spatial scale data on effort and catch information for this particular area and time

Intermittent days off (sundays)

Precise estimates of effort per day. Requires an assumption that if a day of the week is closed, that effort will not simply shift to other days. By only closing one day per week, we will be unable to justify reduced discards since folks will likely fish for other things on the day fishing is closed to stripers and shifting effort to other days of the week will compensate for closed day.

Eliminate tournament fishing with live baitThis one we need to explore. Not sure what kind of data we have on tournaments. Conservation benefit would likely be low

Fishing & Boating ServicesSport Fisheries Advisory Commission – September 24, 2019

1

Striped Bass Management• Current Circle Hook Regulation – Expires December 16

This includes the 19 inch minimum size limit

• ASMFC – August Meeting Highlights

• ASMFC – September 25th / October 3rd - Public Hearings

• State of Maryland – Where do we go from here?

Discussion of Timeline and Procedures through February 2020


2

Circle Hook Regulation / 19 Inch Minimum• Department intends to propose regulations to remove the

sunset provision on the 2018 regulation which mandated the use of circle hooks when chumming or live-lining.

• This regulation also lowered the minimum size to 19 in.• Formally scoped at SFAC/TFAC October meetings• Effective in the spring / before the summer/fall season


3

ASMFC – August Meeting Highlights• Approved Addendum VI for Public Comment• Long discussion on Conservation Equivalency• This Addendum allows states a lot of flexibility when

deciding on how to take the required reductions• Recreational Measures• Allocation of reduction to each of the sectors (Comm/Rec)

Draft Addendum VI for Public Comment

Public Hearing:Maryland

September 25 and October 3, 2019

2.2.1 Status of the Stock

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(100

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etric

tons

)

Female SSB (mt) Recruitment SSB Threshold SSb Target

SSBThreshold = SSB1995 = 91,436 mt

2.2.1 Status of the Stock

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F Threshold

F Target

2.2.3 Status of the Fishery

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10.011.0

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Commercial harvestCommercial DiscardsRecreational HarvestRecreational Release Mortality

Figure 3.

Total Removals2017 = 7.1 million fish 2018 = 5.8 million fish

Management Options Decision Tree

Option 1:Status Quo

3.1

Prop

osed

Man

agem

ent S

cena

rios

Option 3:Commercial = -1.8% Recreational = -20%

Option 2:Commercial = -18%Recreational = -18%

No change in management; fisheries continue to operate under Addendum IV

Commercial quota (-18%)

Ocean

Recreational Fishery (-18%) Chesapeake Bay

Commercial quota (-1.8%)

Ocean


Sub-options 2A

Sub-options 3B

Sub-options 3A

Sub-options 2B


Option 1:Status Quo

3.1

Prop

osed

Man

agem

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rios





Ocean



Ocean


Sub-options 2A

Sub-options 3B

Sub-options 3A

Sub-options 2B

Option 2: Commercial Quota -18%Addendum IV

Quota2017

Harvest18%

ReductionStateChesapeake Bay Commercial Quota^

Maryland 1,471,888 1,439,760 1,206,948PRFC 583,362 472,719 478,357

Virginia 1,064,997 827,848 873,298Chesapeake Bay Total 3,120,247 2,740,327 2,558,603

Ocean Commercial QuotaMaine* 188 - 154

New Hampshire* 4,313 - 3,537Massachusetts 869,813 823,409 713,247Rhode Island^^ 182,719 175,312 148,889Connecticut** 17,813 - 14,607

New York 795,795 701,216 652,552New Jersey**^^ 241,313 - 177,048

Delaware 145,085 141,800 118,970Maryland^^ 98,670 80,457 74,396Virginia 138,640 133,874 113,685

North Carolina 360,360 - 295,495Ocean Total 2,854,706 2,056,068 2,312,579

Option 2: Ocean Recreational Fishery

Sub-Options 2-A: achieves at least an 18% reduction• All jurisdictions would implement

Sub-Option

Bag Limit

SizeLimit

Season andTrophy

Fish/Season

% change from 2017

Harvest Release Mortality

Total Removals

2-A1 1 35” minSame seasons

and trophy season as 2017^

(see Appendix 1)

-43% +3% -18%2-A2 1 28”-35” slot -46% +3% -19%2-A3^ 1 30”-38” slot -44% +3% -18%2-A4^ 1 32”-40” slot -49% +4% -21%

Option 2: Chesapeake Bay Rec Fishery

Sub-Options 2-B: achieves at least an 18% reduction• MD, PRFC, DC and VA would implement

Sub-Option

Bag Limit

SizeLimit

Season andTrophy Fish/Season

% change from 2017


Total Removals

2-B1 1 18” min Same seasons and trophy season as 2017 (see

Appendix 1)

-40% +4% -20%

2-B2 2 22” min -34% +4% -18%

2-B3 2 18”-23” slot Same seasons as 2017 butwithout trophy fish season^

-36% +5% -19%

2-B4 2 20”-24” slot -35% +5% -19%


Option 1:Status Quo

3.1

Prop

osed

Man

agem

ent S

cena

rios





Ocean



Ocean


Sub-options 2A

Sub-options 3B

Sub-options 3A

Sub-options 2B

Option 3: Commercial Quota -1.8%Addendum IV

Quota2017

Harvest1.8%

ReductionStateChesapeake Bay Commercial Quota^

Maryland 1,471,888 1,439,760 1,445,394PRFC 583,362 472,719 572,861

Virginia 1,064,997 827,848 1,045,827Chesapeake Bay Total 3,120,247 2,740,327 3,064,083

Ocean Commercial QuotaMaine* 188 - 185

New Hampshire* 4,313 - 4,235Massachusetts 869,813 823,409 854,156Rhode Island^^ 182,719 175,312 178,304Connecticut** 17,813 - 17,492

New York 795,795 701,216 781,471New Jersey**^^ 241,313 - 212,026

Delaware 145,085 141,800 142,473Maryland^^ 98,670 80,457 89,094Virginia 138,640 133,874 136,144

North Carolina 360,360 - 353,874Ocean Total 2,854,706 2,056,068 2,769,454

Option 3: Ocean Recreational Fishery

Sub-Options 3-A: achieves at least an 20% reduction• All jurisdictions would implement

Sub-Option

Bag Limit

SizeLimit

Season andTrophy

fish/season

% change from 2017


Total Removals

3-A1 1 36” min Same seasons and trophy

season as 2017^

(see Appendix 1)

-48% +4% -20%3-A2 1 28”-34” slot -52% +4% -22%3-A3 1 30”-37” slot -51% +4% -21%3-A4 1 32”-40” slot -49% +4% -21%

Option 3: Chesapeake Bay Rec Fishery

Sub-Options 3-B: achieves at least an 20% reduction• MD, PRFC, DC and VA would implement

Sub-Option

Bag Limit

SizeLimit

Season andTrophy

Fish/Season

% change from 2017


Total Removals

3-B1^ 1MD: 19" minPRFC, DC, VA:

20" min

Same seasons and trophy season as 2017

(see Appendix 1)

-48% +4% -29%

3-B2 1 18” min -40% +4% -20%3-B3 2 23” min Same seasons as 2017

except the trophy season starts

no earlier than May 1

-42% +6% -20%3-B4 2 18”-22" slot -48% +6% -21%3-B5 2 20”-23" slot -47% +6% -20%

3-B6 2 22”-40" slot

Same seasons as 2017; same trophy season and minimum sizes

except with a 40” max size limit

-39% +5% -21%


17

State of Maryland – Where do we go from here?• Stakeholder Feedback – Solicited this Summer (Handouts)• Quantifiable / Non-Quantifiable Solutions determined• We are working on possible management actions to

achieve the required reduction of 18% – 20%


18

Possible Management Actions• No Pre-Season Catch and Release (March and April)• May 1st Start of the Trophy Season• July/August (Wave 4) Closure – No Targeting (21days)• Limit Fishing Hours to the Morning – Rest of Wave 4• Eliminate the Extra Boat Fish for Charters• Shorten the Season in December• 1 Fish Bag Limit• Size Limit Modification – Slot Limit /Drop to 18 inches


19

Timeline and Procedures through February 2020• September 25th and October 3rd – Public Hearings• October 11th – Technical Committee Meeting• October 22nd and 24th – Scope Circle Hooks/Spring Trophy

changes at SFAC/TFAC…Also discuss in more detail the Potential Management Actions (with reductions numbers)

• October 30th – ASMFC Board Meeting• End of November – Submit or CE Proposal to ASMFC• Early January – Technical Committee Review of Proposal• Late January / Early February – Board Consideration of our CE

Proposal

Fishing for Invasive Fishes - calendarmedia.blob.core ... · 1. Big River freshwater fish, deep holes and often found over hard bottom habitats 2. Can be abundant 3. Primarily eats

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