Live bait in Maryland: What we know, don`t know, but need to

Live bait in Maryland: What we know, don’t know, but need to
know to effectively manage this invasive species vector
Jay Kilian and Ronald Klauda
Maryland Department of Natural Resources
Resource Assessment Service
Annapolis, Maryland
Live bait vector management in Maryland (pre-2007)
Bait bucket
introductions
in the
Mid-Atlantic
Approximately 47 freshwater species introduced as
bait in Atlantic slope drainages (P. Fuller, USGS)
What we know…
• Bait-related introductions have been widespread in Maryland
• Bait-related introductions have been recognized since the late 1950s
• Now established in Maryland ecosystems due to bait use –
ƒ 6 fishes (most recent was Mimic Shiner – confirmed 2012)
ƒ 5 crayfishes
ƒ ~ 9 earthworms
Virile Crayfish (Orconectes virilis)
• First documented in 1959 from one river basin
• Currently Maryland’s most widespread bait species
• Displacing native crayfishes from entire watersheds
This is what happens with
NO management!
This is what we need to
prevent from happening
again!
Rusty Crayfish (Orconectes rusticus)
• Most notorious invasive bait species
• First discovered in MD in 2007
This discovery provided the impetus for bait and angler surveys
We conducted two surveys to answer these questions:
Telephone survey of Maryland bait shops
To determine:
1) what types of live bait are sold
2) the source of live bait
Mail survey of Maryland freshwater anglers
To determine:
1) how many anglers use live bait
2) where anglers get their bait
3) how anglers dispose of unused live bait
Telephone survey of Maryland bait shops
Methods:
• Called 71 Maryland bait shops
• Shop owners/managers were asked:
• Do you sell live bait?
• What types of live bait do you sell?
• What is your top-selling bait?
• Where do you purchase your live bait (e.g. wholesalers, internet, etc.)
• Randomly-selected 12 bait shops (3 from each of 4 fisheries management regions)
• Visited and purchased bait from these twelve shops
• All earthworms, crayfishes, fishes, and crabs purchased were identified to species
Telephone
Telephone Survey
Survey of
of Maryland
Maryland Bait
Bait Shops
Shops
Results:
76% of bait shops sold live bait
Bait types sold:
• Worms (94% of bait shops) - 11 types
• Fishes (76% of bait shops) – 9 types
• Crabs/ Shrimp (52% of bait shops) – 4 types
• Crayfishes (9% of shops) – sold as small, medium, and large
Telephone
Telephone Survey
Survey of
of Maryland
Maryland Bait
Bait Shops
Shops
Results:
Sources of bait to MD bait shops:
Internet not a source…Good News!
Internet
Crabs/Shrimp
Self Caught
Worms
Crayfishes
Local Collector
Fishes
Wholesale Distributor
0
20
40
60
80
100
Percent of Bait Shops Selling Specific Bait Type
• Maryland bait shops reported purchasing from 24 wholesale distributors
• 23 out of 24 were from out-of-state; many were out of Mid-Atlantic region
Telephone
Telephone Survey
Survey of
of Maryland
Maryland Bait
Bait Shops
Shops
Results:
Non-native species purchased from Maryland bait shops ( * known invasive species)
Category
Genus/Species
Retail Name
Status
Worms
Lumbricus terrestris
Nightcrawlers
Canadian nightcrawlers
Green nightcrawlers
Green worms
Nitro-worms
Non-Native*
L. rubellus
Red worms
Non-Native *
Eisenia fetida
Red wigglers
Trout worms
Non-Native
Carassius auratus
Black saltys
Non-Native *
Pimephales promelas
Fathead minnows
Non-Native
Crayfishes
Procambarus sp. (zonangulus)
P. clarkii
Orconectes virilis
Crayfish
Non-Native *
Crabs
Carcinus maenas
Green crab
Non-Native *
Fishes
This list does NOT include possible hitchhikers!
Mail Survey of Maryland Freshwater Anglers
Methods:
• Randomly selected 10,000 (approx. 6%) freshwater anglers
• Selection included resident and non-resident anglers
• Stratified selection: 23 counties, Baltimore City, and all other
states combined
• Survey questions included:
• What types of live bait do you use?
• Where do you get your live bait? (e.g. self-caught, bait shop, internet, etc)
• Where do you fish with live bait? (e.g. creek, river, small pond, reservoir)
• What do you do with your unused live bait?
Mail
Mail Survey
Survey of
of Maryland
Maryland Freshwater
Freshwater Anglers
Anglers
Methods:
• Answers were categorized by bait type (adapted from Keller et al. 2007).
Example:
If you use live bait, where do you get it? (Circle one or more answer for each bait category that applies to you)
Minnows/Shiners
a. catch my own
b. bait/tackle shop
c. internet
d. convenience store
e. vending machine
f. other
______________
___________________
Earthworms/
Nightcrawlers
a. catch my own
b. bait/tackle shop
c. internet
d. convenience store
e. vending machine
f. . other
_______________
_____________________
Crayfish
a. catch my own
b. bait/tackle shop
c. internet
d. convenience store
e. vending machine
f. other
_________________
______________________
Grubs/Mealworms/
Waxworms/Maggots
a. catch my own
b. bait/tackle shop
c. internet
d. convenience store
e. vending machine
f. other
_______________
____________________
Other
(bait type you specified in
Question 3)
a. catch my own
b. bait/tackle shop
c. internet
d. convenience store
e. vending machine
f. other
__________________
_______________________
• Anglers were allowed to choose more than one answer
• Numbers of anglers using bait were extrapolated from sub-sample response
Mail
Mail Survey
Survey of
of Maryland
Maryland Freshwater
Freshwater Anglers
Anglers
Results:
• 9,236 surveys were successfully delivered
• 2,237 (24%) survey forms returned
Anglers (X1000)
• 64% of anglers use live bait
Total Angler Population (157,118)
160
140
120
100
80
60
40
20
0
LiveBait
Minnow
Worms
Crayfish
Grubs
Other
Mail
Mail Survey
Survey of
of Maryland
Maryland Freshwater
Freshwater Anglers
Anglers
Results:
Where do anglers get their live bait?
Percent of Anglers
100
Self-Caught
75
Bait Shop
Convenience Store
50
Vending Machine
Internet
25
Other
0
Fish
Worms
Crayfish
Grubs
Other
• Bait shops were the largest source of all bait types (except crayfish)
Mail
Mail Survey
Survey of
of Maryland
Maryland Freshwater
Freshwater Anglers
Anglers
Results:
How do anglers dispose of unused bait?
Percent of Anglers
100
75
Release in Water
Release on Shore
Save For NextTrip
50
Dispose in Trash
Dispose Other
25
0
Fish
Worms
Crayfish
Grubs
Other
• Disposal of bait varied by bait type; anglers more readily released aquatic than
terrestrial bait types
• 65% and 69% of anglers released live fishes and crayfishes
• 18% and 10% of anglers released live earthworms and grubs
What we know…
• MD bait shops are a source of non-native, potentially invasive species
• Most bait sold in shops originates outside of MD and, in some cases
outside of the Mid-Atlantic region
• The release of unused bait is a common practice among MD anglers – anything
imported into MD and sold as bait, will likely be released
• Anglers will hasten the spread of invasive species introduced through other
vectors (e.g., aquarium/pet trade)
The bait industry is dynamic, so….the sources and types of live bait sold in Maryland
are likely to change.
Live bait vector management in Maryland (post-2007)
We’ve moved from this…
to this.
Where to interrupt the live bait pathway in Maryland?
Aquaculture/ Bait Harvesters (?)
Wholesale Distributors (24 as of 2009)
Retail Bait Shops (71 as of 2009)
Convenience and mega-stores (?)
Anglers (>150,000)
Recipient
Ecosystem
Where to interrupt the live bait pathway in Maryland?
Aquaculture/ Bait Harvesters (?)
Wholesale Distributors (24 as of 2009)
Retail Bait Shops (71 as of 2009)
Convenience and mega-stores (?)
Anglers (>150,000)
Recipient
Ecosystem
Where to interrupt the live bait pathway in Maryland?
Aquaculture/ Bait Harvesters (?)
Wholesale Distributors (24 as of 2009)
Retail Bait Shops (71 as of 2009)
Convenience and mega-stores (?)
Anglers (>150,000)
Recipient
Ecosystem
Interrupting the vector at the bait shop…
Steps we have taken:
• Banned the import and possession of some invasive bait
(Aquatic Nuisance Species Regulation)
Steps we could take:
• Require that all retail bait distributors register with MDNR
• Engage bait shops; form partnerships
• Require that all retail bait shops provide sources and types of bait being sold
• Educate all retail distributors on current MD regulations
• Improve enforcement of regulations and monitoring
We need greater oversight of the bait industry
Interrupting the vector at the angler…
Steps we have taken:
• Prohibited the transfer of invasive species between watersheds
(e.g., Virile Crayfish, Red Swamp Crawfish)
• Banned the use of live crayfish in three river basins where
Rusty Crayfish is established
• Increased efforts to inform anglers and change their behavior
But, this has been piecemeal and too small to be effective!
We know we need a LARGE and sustained effort to change angler behavior
What we don’t know:
• How to effect change in the angling community?
• What message will be most effective?
• How to spread the message most effectively?
• How to convince anglers that killing unused bait is humane?
Challenges we face:
1) Prevent import and sale of invasive bait species
2) Prevent the further spread of invasive bait species already established
3) Do both of these without adequate funding or the political will to make this a
priority!
• MDNR has no full time AIS staff
• AIS management is mostly just a side “hobby”
• We need to find consistent source of funding and partners
We are on the right path, but our progress is painfully slow!