OCCURRENCE AND DISTRIBUTION

of

CYANOBACTERIA

on the

GULF STREAM REEF SYSTEM,

BOYNTON BEACH, FLORIDA

Prepared September 2003

by Ed Tichenor
CONTENTS

Section

1.0 INTRODUCTION

1.1 Background

1.2 Purpose

1.3 Scope

2.0 ALGAE BLOOM

3.0 DELINEATION OF CYANOBACTERIA

3.1 Methodology

3.2 Observations

4.0 CONCLUSIONS AND RECOMMENDATIONS

LIST OF APPENDICES

Appendix Description

A Dive Log Book Excerpts

B Photograph #1Lynn’sReef

Photograph #2 Cyanobacteria

Photograph #3 Cyanobacteria

Photograph #4 Cyanobacteria

Photograph #5 Atlantic Spadefish

LIST OF FIGURES

Figure Description

#1 Location Map, Gulf Stream Reef

#2 Site Map, Gulf Stream Reef

#3 Occurrence and Distribution of Cyanobacteria March 23, 2002

#4 Occurrence and Distribution of Cyanobacteria September 14, 2002

#5 Occurrence and Distribution of Cyanobacteria November 30, 2002

#6 Occurrence and Distribution of Cyanobacteria March 16, 2003

#7 Occurrence and Distribution of Cyanobacteria September 13, 2003

(i)
1.0 INTRODUCTION

1.1 Background

The Gulf Stream Reef is a coral reef system located southeast of the Boynton Beach Inlet,

approximately one mile offshore (26 31 00o N, 80 02 00o W) between the communities of

Delray Beach to the south and Lake Worth to the north (Figure 1). Ranging in depth

from approximately 40 to 85 feet below the ocean surface, the reef is approximately three

miles long. Sitting in close proximity to the Gulf Stream the reef is nearly always awash

with a strong north current. It is heavily populated with hard and soft corals, fish,

sponges and other invertebrate life.

ThereefisreferredtoasbothGulfStreamandLynn’sbylocals.Nodesignationsappear

for reefs along this section of coastline on NOAA charts. A publication by the Palm

Beach County Department of Environmental Protection refers to a reef in this area as

Lynn’s,butitisunclearifthereferenceisforaportionortheentirereef.Inaddition,

popular dive locations on the reef are also named (Figure 2). To add to possible

confusion, a dive spot in the southwest quadrantiscalledGulfStreamandLynn’sisa

dive spot designation on the northeast end of the reef. For purposes of this presentation

the entire reef system is referred to as Gulf Stream Reef.

The Gulf Stream Reef is found near the northern limit of the coral reef tract which runs

from the Dry Tortugas, through the Florida Keys and north to Palm Beach County.

While not as well known, Gulf Stream hosts the same abundant biodiversity found on the

morefamoussouthernreefs.Lynn’sReef(AppendixB,photo1) located in the northeast

quadrantofGulfStreamhasbeenthefocusofnumerousarticlesextollingit’sbeautyand

pristineconditions(SkinDiver,SouthernDiver1998CollectorsEdition)“...siltfreeand

sparkling[Lynn’s]...rivalsthebest[coralreef]conditionsfoundanywhere.”Miami

Herald,December13,2002,OutdoorSection;“PalmBeach’sreefs...havegained

internationalrecognition”.

Gulf Stream Reef is visited by 1000s of scuba divers each year aboard private boats and

from six to ten dive charters operating out of the Boynton Beach Inlet. Due to the nearly

constant north current scuba divers are attracted to this area for what is referred to as

“driftdiving”,anactivitywhichcanonlybeexperiencedinafewworldlocations.In

addition, the reef system is the basis for a large sport fishing and commercial fishery.

Theseandancillarybusiness’provideasignificantcontributiontothelocaleconomy.
1.2 Purpose

In early 2002 an algae bloom (Cyanobacteria) began to develop in thevicinityofLynn’s

Reef. The bloom is characterized by red filaments of algae which adhere to bottom

growth, such as sponges and corals (Appendix B, photos 2, 3 and 4). Over a period of the

next few months the area affected expanded and the coral began to show signs of stress.

The spread of the Cyanobacteria and resulting damage to the coral reef prompted an

initial investigation based on visual observations designed to determine the extent of the

problem. Recreational scuba divers from the local community have collaborated to

generate this report of their findings with the intent of making these data available to

regulatory, municipal and scientific organizations. It is hoped that further investigation

and possible remediation may result once knowledge of this situation comes to light.

1.3 Scope

The investigation included the collection of qualitative data based on visual observations

made during more than 100 scuba dives conducted in the study area from March 2002 to

September 2003. Inspection dives lasted about one hour and generally covered

approximately 0.25 to 0.5 miles of reef. Data obtained from these weekly dives were

used to generate site maps (Figures 3 through 7) delineating the extent of the algae

bloom.
2.0 ALGAE BLOOM

The appearance of the red filamentous algae was first noted in the shallower (40-50ft.)

areas of the Gulf Stream Reef early in 2002. The algae, initially confined to the vicinity

ofLynn’sReefhassincebeenidentifiedasCyanobacteria.

Cyanobacteria, formerly classified as blue-green algae, employ chlorophyll and other

pigmented compounds to convert sunlight into metabolites. Cyanobacteria blooms are

well documented worldwide and can be considered a visible measure of health in a reef

community. The Cyanobacteria ultimately kill the coral polyps by physically restricting

thecoral’sabilitytofeedandbyblockingsunlightpreventingphotosynthesis.These

blooms result from exposure to elevated levels of nutrients such as phosphorous and

nitrogen compounds. Such nutrients can be the result of improperly treated sewage, urban

and agricultural run-off, an offshore up-welling of contaminated groundwater percolating

from the ocean floor or up-wellings of nutrient rich deep ocean water.

Cyanobacteria proliferation is an early sign of deteriorating environmental conditions,

allowing for corrective measures to be taken before the death of a reef community occurs.
3.0 DELINEATION OF CYANOBACTERIA BLOOM

3.1 Methodology

On March 23, 2002, as it became obvious that the Cyanobacteria bloom was not abating,

but rather increasing in size, local scuba divers began to record their visual observations.

Weekly dives were conducted and dive log/field notes were recorded documenting the

presence or absence of the algae and water temperature at specific reef locations. This

process has continued through September 2003 and is the basis of this report.

Areas of investigation were located by the dive boat operator using GPS measurements to

obtain latitude and longitude coordinates. Areas inspected during the course of this study

included most of the Gulf Stream Reef system. However, the total reef was never

examined during any one dive outing. Generally, two locations covering approximately

0.5 to 0.75 miles each were incorporated in a dive trip. Most dives were performed along

the shallower (45 to 65 ft.) inside, western reef line.

Less frequent dives were conducted on the Western Edge and Jump, and the deeper

(85ft.), Outside Fingers (Figure 2). Therefore, data from these areas are limited. No

dives were made during this study at Sawfish Circle. Observations recorded in the dive

logs (Appendix A) were used to generate site maps delineating the occurrence,

distribution and abundance of the Cyanobacteria (Figures 3 through 7).

3.2 Observations

The Cyanobacteria in general was first detected attached to soft corals such as octocoral

and sea fans (Appendix B, Photo 2, 3 and 4). As growth continued the algae began to

blanket most sessile organisms on the reef which resulted in damage to or the death of

many of the soft corals found in the Gulf Stream system. The period of time from initial

infestation to smothering and subsequent death of the soft corals has been observed to

occur in as little as a few months.

The delineation site maps (Figures 3 through 7) provide a graphic representation of the

distribution and concentration of the Cyanobacteria. Areas of the reef most heavily

affected are in the shallower 40 –65 ft. depths. The spread of the bloom is most striking

from the period March 2002 (Figure 3) to November 2002 (Figure 5) during which time

the algae spread nearly the entire three mile length of the reef and involved most

locations in the 40 –65 ft. range.

During the winter of 2002/2003 the bloom receded (Figure 6). However, during the

summer of 2003 (Figure 7) the area affected again expanded. It should be noted that

during the winter decrease in size the bloom never returned to within the boundaries

where it was first encountered.
As of September 2003 the Cyanobacteria coverage is the most extensive it has been since

firstobservedduringMarch2002.Areasonthenorthendofthereef,suchasLynn’s

have been infested for 18 months and are heavily damaged. The most recent (September

2003, Figure 7) observations have detected the occurrence of Cyanobacteria on the

deeper (80ft.) eastern reef limit for the first time (Appendix B, photo 3).

In addition to the observations made on the Gulf Stream Reef, Cyanobacteria was also

found on Delray Ledges, a reef one nautical mile south of the investigation area (Figure

1). However, on a dive at Delray Ledges conducted on September 20, 2003, no

Cyanobacteria was found.

Curiously, proliferation has not been detected to date on Casino and Horseshoe Reefs

found 6.0 nautical miles to the north. A fact which may be key in understanding the

dynamic of nutrient loading likely responsible for the current algae bloom.
4.0 CONCLUSIONS AND RECOMMENDATIONS

The Cyanobacteria bloom is persistent and does not appear to be abating. Except for

some seasonal fluctuation (Figures 5, 6, 7) the extent of spatial coverage and damage to

the reef community has steadily increased since March 2002. Damage to many key reef

organisms has occurred in the 18 months since the bloom first began. With the death of

many coral species the reef system will no doubt decline and no longer be able to host the

diversity of life once found there.

Schoolsof1000sofAtlanticSpadefish(AppendixB,Photo5)commononLynn’sReef

priortothebloomarenolongerpresent.GulfStream’ssponges,whichinsomelocations

are covered with algae are a food source for a resident sea turtle population. The reef is

also a staging area for transient populations during the summer mating/egg laying season.

While there is no evidence to suggest a connection, the decline of the local lobster fishery

is coincident with the arrival and spread of the Cyanobacteria.

In order to determine the cause of the bloom analyses need to be performed to help

identify the possible source(s) and extent of the suspected nutrient loading. This aspect of

the investigation could include chemical analysis of water samples as well as a search of

public records to determine compliance with federal and state NPDES (National

Pollution Discharge Elimination System) permits by local and up-current sewer plant

operators. In addition, further mapping and expansion of the investigation area should be

performed to aid in understanding the scope of the problem.

The Gulf Stream Reef system is a valuable asset, generating millions of dollars a year for

the local economy. The presence of the Cyanobacteria is an early indicator of declining

health. Fortunately, if the excess nutrients can be reduced or eliminated it is likely the

reef system has not suffer enough damage to preclude recovery.
APPENDIX A

Dive Log Book Excerpts(1)

March 2002 to September 2003

Date: 3/23/02

Dive #: 744

Water temp. oF: 75

Location:CastleLedge/Lynn’sReef

Observations:AreabetweenCastleLedgeandLynn’smuchredfilamentousalgae(2) on dead octo coral. Have seen this

on recent dives; getting worse.

Date: 5/18/02

Dive #: 760

Water temp. oF: 78

Location:CastleLedge/Lynn’sReef

Observations: Red algae still present inside reef line.

Date: 9/7/02

Dive #: 776

Water temp. oF: 85

Location: Jump

Observations: Red algae has spread this far north.

Date: 9/14/02

Dive #: 777

Water temp. oF: 83

Location: Black Condo

Observations: Red algae has spread this far south.

________________________________________________________________________________________________

Date: 9/21/02

Dive #: 779

Water temp. oF: 85

Location: Black Condo

Observations: Extensive Red algae
Date: 9/28/02

Dive #: 781

Water temp. oF: 83

Location: Delray Ledge

Observations: Filamentous red algae here.

________________________________________________________________________________________________

Date: 9/28/02

Dive #: 782

Water temp. oF: 84

Location: North end of Clubhouse

Observations: Extensive red algae, mostly on deep water sea fans. Smothering reef.

------------------------------------------------------------------------------------------------------------

Date: 10/5/02

Dive #: 783

Water temp. oF: 82

Location:Jerry’sNo-name north to Castle Ledge

Observations:Redalgaeeverywhere,lessonJerry’s;CastleLedgeheavy.

________________________________________________________________________________________________

Date: 10/5/02

Dive #: 784

Water temp. oF: 82

Location: West edge of Table tops

Observations: Very little red algae here.

________________________________________________________________________________________________

Date: 11/30/02

Dive #: 793

Water temp. oF: not recorded

Location: Black Condo

Observations: Red algae blankets everything.

________________________________________________________________________________________________
Date: 11/30/02

Dive #: 794

Water temp. oF: not recorded

Location: West edge of Table tops

Observations: Red algae in now here.

________________________________________________________________________________________________

Date: 3/1/03

Dive #: 805

Water temp. oF: 69

Location: Casino

Observations: No red algae here.

Date: 3/1/03

Dive #: 806

Water temp. oF: 70

Location: Horseshoe

Observations: No red algae here.

Date: 3/8/03

Dive #: 807

Water temp. oF: 73

Location: Clubhouse south of Black Condo

Observations: Little to no red algae.

________________________________________________________________________________________________

Date: 3/8/03

Dive #: 808

Water temp. oF: 74

Location: Table Tops to Briney Breezes

Observations: Red algae present.
Date: 3/16/03

Dive #: 809

Water temp. oF: 68

Location: Black Condo

Observations: Red algae present.

________________________________________________________________________________________________

Date: 3/16/03

Dive #: 810

Water temp. oF: 68

Location: Inside west edge of Briney Breezes

Observations: Red algae present.

Date: 4/26/03

Dive #: 825

Water temp. oF: 75

Location:Lynn’sReef

Observations: Red algae present.

Date: 7/12/03

Dive #: 849

Water temp. oF: 82

Location: Black Condo

Observations: Red algae showing up here.

Date: 7/19/03

Dive #: 850

Water temp. oF: 77

Location: Casino

Observations: No red algae present.
Date: 7/19/03

Dive #: 851

Water temp. oF: 82

Location: Horseshoe

Observations: No red algae present.

________________________________________________________________________________________________

Date: 7/22/03

Dive #: 853

Water temp. oF: 82

Location:BrineyBreezestoLynn’sReef

Observations: Red algae heavy and extensive.

Date: 7/23/03

Dive #: 854

Water temp. oF: 79

Location: Grouper Hole

Observations: No red algae present.

Date: 8/9/03

Dive #: 860

Water temp. oF: 84

Location:Jerry’sNo-nametoLynn’sReef

Observations:Redalgaepresent@ Jerry’sincreasestoheavyandextensive@ Lynn’s.

Date: 8/24/03

Dive #: 863

Water temp. oF: 83

Location: Gulfstream

Observations: Some red algae present, but not extensive.
Date: 8/24/03

Dive #: 864

Water temp. oF: 83

Location: Black Condo to Briney Breezes

Observations: Red algae present, but not severe @ Blk Condo increases to heavy @ Briney Breezes.

________________________________________________________________________________________________

Date: 9/13/03

Dive #: 866

Water temp. oF: 82

Location: Outside Fingers west to Black Condo

Observations: Outside @ 80 –85 ft. algae present, but spotty and not extensive, more @ 65 ft. and reef tops. Inside @

Blk Condo extensive growth.

_______________________________________________________________________________________________

Date: 9/13/03

Dive #: 867

Water temp. oF: 82

Location: Clubhouse to Gulfsrteam

Observations: Heavy algae growth on sea fans and soft corals. Photos of algae taken on both dives today.

Date: 9/20/03

Dive #: 868

Water temp. oF: 81

Location: Delray Ledge

Observations: Not a trace of Cyanobacteria.

Date: 9/20/03

Dive #: 869

Water temp. oF: 81

Location: Clubhouse to Black Condo

Observations: From southern end of reef Cyanobacteria begins 1/4 to 1/3 of the way into Clubhouse and increases to

. the north.

(1) More than 100 dives were completed in the investigation area between March 2002 and September 2003.

Only excerpts from dive logs where a change (increase or decrease) in the Cyanobacteria coverage was

recorded have been cited.

(2) All references to algae refer to Cyanobacteria unless otherwise stated.
APPENDIX B

PHOTOGRAPHS
PHOTO #1

Lynn’sReef

(Prior to Cyanobacteria bloom)

photo by Sandra Edwards
PHOTOS #2 and #3

Cyanobacteria

Gulf Stream Reef

(September 2003)

photos by Ed Tichenor
PHOTO #4

Cyanobacteria

Gulf Stream Reef

Outside Fingers

(82 ft. below surface)

Deep Water Sea Fan

(September 2003)

photo by Ed Tichenor
PHOTO #5

Atlantic Spadefish

Lynn’sReef

( No longer common on reef)

photo by Peter Schulz
FIGURES