How important is structure?

Studying the effects of habitat complexity on coral community diversity and abundance

Brittany Huntington,

PhD candidate

University of Miami

This study will use the Long Key Bridge Rubble, an existing artificial reef structure in the Florida Keys, to explore the role of habitat complexity and spatial configuration in structuring coral communities.
Coral reefs are valued as unique ecosystems with high levels of biodiversity; however, little is known about which features of reef structure are crucial in supporting the diverse coral assemblages found on these reefs. While studies have linked greater reef complexity to greater fish diversity and abundance, the role of structural habitat complexity on the stony coral community remains unclear. By utilizing an existing artificial patch reef array with varying physical structure and a distinct spatial arrangement among patches, we will test the hypotheses that greater habitat complexity (‘habitat heterogeneity hypotheses’) and great proximity to neighboring patches supports greater coral diversity and abundance. This approach capitalizes on the unique structural variations within an existing artificial reef complex to test predictions of habitat complexity that would be difficult, if not impossible, to manipulate on natural reefs. In addition, we will be able to test the impacts of patch spatial arrangement on recruitment rates and coral abundance by monitoring both ‘edge’ and ‘middle’ patches within the artificial reef complex.
Field sampling will consist of extensive surveys of existing coral reef communities across similarly sized artificial patches of varying substrate complexity and spatial configuration. Percent cover of benthic organisms and coral species richness will be determined for each patch. Lastly, rates of coral recruitment will be measured using coral settlement tiles attached to each study reef.
Initial mapping of artificial patches was completed in March 2009, and complexity of each patch was recorded. In mid-March, a 6-member dive team conducted the initial sampling of the 16 study patches. Fish counts, benthic cover, coral demography and patch complexity data was taken for each patch. Recruitment tiles could not be hammered into the concrete of the artificial reefs, hence the tiles were not deployed. We are currently testing and building alternative rigs to hold recruitment tiles for deployment at our study reefs and hope to install the tiles in early May 2009.

Given the current degradation of reefs from bioerosion, coral disease and habitat fragmentation, there is a pressing need to elucidate the importance patch quality and spatial configuration to coral community dynamics. Results from this study will enhance our ability to manage reefs for abiotic features that contribute to robust coral communities, shaping future restoration efforts and design of coral reef reserves.

Studying Kin Conflict in the Elongate Twig Ant (Pseudomyrmex gracilis)

Volker Schmid, PhD student

University of Regensburg, Germany

My research topic is the social behaviour of ants, especially conflicts among members of the same colony. Because all ants within a colony are related to each other to a more or less high degree, each colony can be regarded as a kind of family. As in human families, conflicts may arise between individuals within a colony over certain matters: e.g. how many resources should be invested in the production of either female or male sexuals (those ants which spread out and reproduce, the females eventually founding new colonies); or who produces the male offspring, which is not necessarily only the queen. In the absence of a queen, evolutionary theory predicts that worker ants begin laying eggs which develop into males (workers usually cannot produce female offspring).

Elongate twig ant sucking honey placed on a leaf in the field (Curry Hammock State Park)

I will be testing this evolutionary theory on the Elongate Twig Ant (Pseudomyrmex gracilis). Native to Mexico, this species invaded Florida during the second half of the 20^th century and can be found today at many locations in disturbed habitats or habitat edges (e.g. along roadsides). Using the Keys Marine Lab as my base of operations, I have collected colonies from various locations throughout the Florida Keys (Long Key State Park, Curry Hammock State Park, and Fort Zachery Taylor State Park). Captured colonies will be taken to Germany where I will continue observations of the social interactions and kin conflict of these ants.

The rest of the KML fleet

R/V MolaMola

25' Parker, center console, modified-V hull
powered by 225hp Yamaha 4-stroke engine
large dive platform and sturdy dive ladder
capacity: 2200 lb or 11 passengers plus a captain

R/V NariNari
18' Parker center console,
powered by 175hp Yamaha 4-stroke engine
capacity: 1800 lb. or 5 passengers plus staff captain
Also available for use by KML scientists without staff captain on board. Inquire about requirements for our boat rental policy

13' Boston Whaler
capacity: 300 lbs or 2 people
powered by an electric start 25hp 4-stroke Mercury
For use near the lab (Long Key and nearshore waters) by KML scientists without staff captain on board

R/V Tiburo is back on the water

KML's R/V Tiburo has a new look these days. This grand old 24' T-Craft has been renovated, reconditioned, and is ready for trips back into Florida Bay. Powered by a 175hp Yahmaha engine, she has 1200 lb maximum capacity or 8 passengers plus a captain. "Tib" offers plenty of open deck space for portable live-wells and gear.

KML's Sea Water Tanks

KML's newly-renovated seawater tank farm is once again ready for education groups and researchers! Coarsely filtered seawater is drawn from the lagoon in front of the wetlab seawall... ...into a holding pond (formerly Shallows 4). Seawater is pulled from the holding pond to fill our various tanks. Over-flow from the holding pond runs directly to the large 220,000 gallon capacity Shallows (formerly Shallows 5) which has an average depth of 32".

We monitor water quality (temp, DO, salinity) daily from 4 locations around the lab: our marina basin, near-shore Florida Bay off our outer seawall, the lagoon near our intake point, and the Shallows. Dissolved oxygen readings in the Shallows have been consistently between 60% and 85% throughout the winter, in spite of dense mats of rack along the seawall.

Phase I of KML's seawater system offers a variety of tanks and wet tables with water flow rates ranging from 300 gal. per hr. to 600 gal. per hr. Water levels in the tanks and tables can be adjusted by variable stand-pipes.

Tanks and tables under lattice shade structure:

A total of 6 wet tables (23"W x 6'L) - 3 outside and 3 under the Wet Lab Pavilion, maximum water depth 8", approx. 60 gal. capacity; ideal for smaller specimens and student group observations

A total of 6 fiberglass tanks (foreground, 26"W x 4'L), maximum water depth 12"; approx. 75 gal. capacity
Two 6' diam. round fiberglass tanks (upper left), maximum water depth 24"; approx. 350 gal capacity
One 8' diam. round fiberglass tank (upper right), maximum water depth 36"; approx. 1100 gal. capacity


4 black livestock tanks (3'W x 5'L), maximum water depth 18"; approx. 1300 gal. capacity
Two 8' diam round tanks, maximum water depth 18", approx. 530 gal. capacity

Tanks exposed to full sunlight:

1 fiberglass raceway (8' long x 21" wide), maximum water depth 12", approx. 120 gal. capacity

4 fiberglass raceways (12' long x 21" wide), maximum water depth 12"; approx. 160 gal. capacity

We anticipate continuing to expand our seawater system to meet the needs of our visitors.

KML's Wet Lab Pavilion is ready to go!

KML staff have continued to work hard throughout the winter on our seawater system and open-air wet lab. We have 2 banks of acrylic aquariums set up inside the wetlab pavilion and plumbed for seawater.
One bank of twelve 15-gal. aquariums (12"W x 24"L x 12" deep) are individually plumbed. These aquariums have the option of using an in-line filtration system which passes through a series of two 20" filter housings. Filter cartridges are available from 50 microns down to 0.35 microns. The second bank of acrylic aquariums are plumbed as 3 flow-through unfiltered seawater systems. The top tier has eleven 2-gal tanks (8" x 8" x 8") and eight 10-gal. tanks (12"W x 15"L x 12" deep). The bottom tier consists of eight 15-gal. (12"W x 24"L x 12" deep) tanks. We have three 75-gal. seawater tables (23"W x 6'3"L x 12" deep) under the wet lab pavilion. Water levels in the tables can be controlled by stand-pipes. Work benches will be set up along the walls to accommodate a variety of separate aquariums and any other necessary equipment. Plenty of open floor space around the tables will accommodate students. Fresh-water sinks (no chemicals down the drains please!) and wash-down hoses are conveniently located around the wetlab.
And if that's not enough, you just can't beat the view from the wet lab and our new sea wall! Sunsets here are spectacular looking out over Florida Bay and the Gulf of Mexico.

Seawater is once again flowing at KML!

But first a brief glimpse behind the scenes these last 4 months:
As another hurricane season drew to an end, the beginnings of the new seawater system unfolded and we could finally focus on the task at hand.

October 2008 behind the KML wetlab

November 2008:
Laying drain pipes, setting up and leveling a variety of tanks and wet tables and plumbing them to the drain.

The pipes had to be carefully covered with dirt - 1 wheel barrow load at a time

Mike and Bill carefully selected and moved large tanks into position with equipment on-hand

A new view of the outer wet lab under the shade lattice with more tanks in place

Old Shallows 4 had to be cleaned out, repaired, sealed, and painted with a special epoxy paint to prepare it for our new seawater holding pond

Bill is the master-mind behind the building of the seawater intake system - affectionately called "the octopus" (well, it really has only 6 legs but it is a very impressive tangle of PVC!) Seawater was actually pumping into Shallows 4 by Christmas!

Three 3-hp Jacuzzi pumps draw water from the lagoon in front of the wetlab through a common uptake manifold to 3" outflow pipes over the 1000 gal settling tank in Shallows 4

Three smaller 3/4-hp Jacuzzi pumps send seawater from Shallows 4 to the various tanks

Seawater lines plumbed to the tanks - Bill had seawater running to the first 10 tanks New Years Eve 2008!! More tanks will soon be on-line and ready to fill.

Cleaning old Shallows 5 took a solid week, with help from several of the Marathon Lab staff. Three years of post-Wilma muck and debris had to be shoveled out. Major cracks were patched, old marcite chipped away and removed. A 2" trash pump sucked out the last of the sludge from the pit.

January 16, 2009 we had water running through the entire system... ....overflowing into the large Shallows (formerly Shallows 5).

A variety of odd critters have already made it their home!

A new boat at the KML dock

Happy New Year at KML! We are excited to announce the newest boat in our fleet, the R/V Diodon (Yes, the spiny puffer fish!).
This 30' Island Hopper, powered by twin Yamaha 4-stroke 250 hp engines, will carry up to 23 snorkelers comfortably to all of the various marine habitats around the Middle Keys.

Thus far, we have taken her on a 24 mile run to East Cape Sable to assist our SEAKEYS staff in tending their northwest Florida Bay C-man station.