Distribution & Habitat Preferences of the , Centruroides hentzi in central Florida State Parks

Abraham Miller PhD & Jennifer Fernandes University of Tampa St. Petersburg College, Tarpon Springs

Scorpion Background

Approx. 1500 worldwide

All are nocturnal predators Glow green under UV light Give birth to live young

Long lived (5+ years) boreus under blacklight All are venomous Photo by Ryan Stork

Scorpion Background

Major constituent of desert Biomass (Polis 1990) With exception of ants and termites, they have the greatest biomass Their biomass is higher than most vertebrates in the desert Paruroctonus boreus under blacklight

Photo by Ryan Stork Importance in Florida

Scorpions are major invertebrate predators

May represent healthy environment Don’t disperse well Require other invertebrates

May be a source for biological control

Centruroides hentzi from Highlands Hammock State Park Why C. hentzi in State parks?

Photo: Guy E. Crauwels (C) www.ntnu.no/ub/scorpion-files/gallery.php Lack of Information Public Information in the Western US Corey & Stout 1990 Corey & Stout 1990

Sampled 12 sites 6 orders; 14 species Scorpion: C. hentzi 4th most abundant of all taxa 86% collected between July-September Juveniles in September No correlation with ground cover

Shelley & Sissom 1995 Questions

What Florida State Parks have ?

How common are scorpions in Florida?

What habitats do they occupy?

What do they prey on? Methods

Blacklight collecting at night between Feb - Nov Used GPS to mark location Scorpion locations were recorded Amount of Moonlight Vegetation Type Vertical height Distance to nearest Pine Tree Distance to nearest Oak Tree Distance to nearest saw palmetto

Laboratory Trial of Tree Preference Scorpions were placed in a large plastic container filled with sand Oak Log & Pine Log were placed vertically in the sand Scorpion location was recorded

What Florida State Parks have scorpions?

5 parks sampled in Central region What Florida State Parks have scorpions?

7 parks sampled in Southwest region Highlands Hammock S.P.

Highlands Hammock S.P.

Highlands Hammock S.P.

Highlands Hammock S.P.

Highlands Hammock S.P.

Habitat Preference

24% found on Saw Palmetto 120

1% found on Cabbage Palm 100

80

20% found on Pine Trees 60

1% found on Oak 40

20

54% found elsewhere (i.e. 0 ground, pine needles, logs, etc.) Pine Oak Cabbage Palm Saw Palm Other

Habitat Preference

24% found on Saw Palmetto 120

1% found on Cabbage Palm 100

80

20% found on Pine Trees 60

1% found on Oak 40

20

54% found elsewhere (i.e. 0 ground, pine needles, logs, etc.) Pine Oak Cabbage Palm Saw Palm Other

Experiment: Habitat Preference Experiment: Habitat Preference Experimental set-up needs to be revised Scorpions disappeared for days at a time, which heavily skewed data Scorpions were seen (active) every 3-14 days Scorpions came out to feed 3-5% of Scorpions are active on any night (Polis 1990) Experiment: Habitat Preference Results: Negative Phototaxis

85% of scorpions 160 143 collected were located in 140 the shadow of the moon 120

100

80

60

40

20 13 14

0 shadow partial shadow moonlight Other Results

Temporal Variation Prey Full Moon at St. Spiders Sebastian 3/7-3/8/12 Caterpillars 7 scorpions – clear Solpugids conditions Moths 3 scorpions after rain Crickets Waning Moon at St. Sebastian 5/21/11 Lacewings 15 captured Moon had not risen yet Unaffected by fire

Other Results

Vertical Stratification Do not burrow Have been seen at 5 meters up a pine tree Gravid Females Found in all areas Females carrying young All found associated with rotting logs on the ground Most (if not all) have termites Possible Food Source Discussion

Pine Trees & Saw Palmettos like offer the best refugia

Poorly drained areas decrease dispersal capabilities

There appears to be seasonality Abiotic Factors Biotic Factors

Abundance Observed 30+/hr along 100m trail

Why not C. hentzi Walk? CETL Funding

Used to set up a lab at the TS campus to get SPC AA and BS students involved in scientific research Need to purchase Black lights Housing containers Building materials for behavioral studies and other experimental supplies Crickets and a terrarium to breed them Light timers Sand Dissecting microscope Acknowledgements

St Petersburg College Florida Biology Class for field help CETL

Florida Department of Environmental Protection Collecting Permit Thanks & Questions