OCCURRENCE AND DISTRIBUTION of CYANOBACTERIA on the GULF STREAM REEF SYSTEM, BOYNTON BEACH, FLORIDA

Prepared September 2003 by Ed TichenorCONTENTS

Section 1.0 INTRODUCTION

1.1 Background 1.2 Purpose 1.3 Scope 2.0 ALGAE BLOO M 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 # 1 L y n n ’ s R e e f

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 an d 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 00 o N, 80 02 00 o 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. T h e r e e f i s r e f

e r r e d t o a s b o t h G u l f S t r e a m a n d L y n n ’ s b y l o c a l s . N o d e s i g n a t i o n s a p p e a r for reefs along this section of coastline on NOAA charts. A publication by the Palm Beach County Department of Environmental Protect ion refers to a reef in this area as L y n n ’ s , b u t i t i s u n c l e a r i f t h e r e f e r e n c e i s f

o r a p o r t i o n o r t h e e n t i r e r e e f

. I n a d d i t i o n , popular dive locations on the reef are also named (Figure 2). To add to possible confusion, a dive spot in the southwest qua d r a n t i s c a l l e d G u l f S t r e a m a n d L y n n ’ s i s a 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 m o r e f a m o u s s o u t h e r

n r e e f s . L y n n ’ s R e e f ( A p p e n d i x B , p h o t o 1) located in the northeast q u a d r a n t o f G u l f S t r e a m h a s b e e n t h e f o c u s o f n u m e r o u s a r t i c l e s e x t o l l i n g i t ’ s b e a u t y a n d p r i s t i n e c o n d i t i o n s ( S k i n D i v e r , S o u t h e r n D i v e r 1 9 9 8 C o l l e c t o r s E d i t i o n ) “

... s i l t f r e e a n d s p a r k l i n g [ L y n n ’ s ]

... r i v a l s t h e b e s t [ c o r a l r e e f ] c o n d i t i o n s f

o u n d a n y w h e r e . ” M i a m i H e r a l d , D e c e m b e r 1 3 , 2 0 0 2 , O u t d o o r S e c t i o n ; “ P a l m B e a c h ’ s r e e f s ... h a v e g a i n e d i n t e r n a t i o n a l r e c o g n i t i o n ”

. Gulf Stream Reef is visited by 1000s of scuba divers each year aboard private boats and from six to ten dive chart ers 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

“ d r i f t d i v i n g ” , a n a c t i v i t y w h i c h c a n o n l y b e e x p e r i e n c e d i n a f e w w o r l d l o c a t i o n s . I n addition, th e reef system is the basis for a large sport fishing and commercial fishery. T h e s e a n d a n c i l l a r y b u s i n e s s ’ p r o v i d e a s i g n i f i c a n t c o n t r i b u t i o n t o t h e l o c a l e c o n o m y .1.2 Purpose

In early 2002 an algae bloom (Cyanobacteria) began to develop in th e v i c i n i t y o f L y n n ’ 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 comm unity 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 knowled ge 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 o f L y n n ’ s R e e f h a s s i n c e b e e n i d e n t i f i e d a s C y a n o b a c t e r i a. 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 re ef community. The Cyanobacteria ultimately kill the coral polyps by physically restricting t h e c o r a l ’ s a

b i l i t y t o f e e d a n d b y b l o c k i n g s u n l i g h t p r e v e n t i n g p h o t o s y n t h e s i s . T h e s e blooms result from exposure to elevated levels of nutrients such as phosphor ous 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 r ecorded 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 us ing 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 locat ions 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 b egan 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 b een 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 bounda ries where it was first encountered.As of September 2003 the Cyanobacteria coverage is the most extensive it has been since

f i r s t o b s e r v e d d u r i n g M a r c h 2 0 0 2

. A r e a s o n t h e n o r t h e n d o f t h e r e e f , s u c h a s L y

n n ’ s have been infested for 18 months and ar e 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 S tream 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. S c h o o l s o f 1 0 0 0 s o f A t l a n t i c S p a d e f i s h ( A p p e n d i x B , P h o t o 5 ) c o m m o n o n L y n n ’ s R e e f p r i o r t o t h e b l o o m a r e n o l o n g e r p r e s e n t

. G u l f S t r e a m ’ s s p o n g e s , w h i c h i n s o m e l o c a t i o n s 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 shou ld 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. o F: 75 L o c a t i o n : C a s t l e L e d g e / L y n n ’ s R e e f O b s e r v a t i o n s : A r e a b e t w e e n C a s t l e L e d g e a n d L y n n ’ s m u c h r e d f i l a m e n t o u s a l g a e (2) on dead octo coral. Have seen this on recent dives; getting worse.

Date: 5/18/02 Dive #: 760 Water temp. o F: 78 L o c a t i o n : C a s t l e L e d g e / L y n n ’ s R e e f Observations: Red algae still present inside reef line.

Date: 9/7/02 Dive #: 776 Water temp. o F: 85 Location: Jump Observations: Red algae has spread this far north.

Date: 9/14/02 Dive #: 777 Water temp. o F: 83 Location: Black Condo Observations: Red algae has spread this far south.

________________________________________________________________________________________________ Date: 9/21/02 Dive #: 779 Water temp. o F : 85 Location: Black Condo Observations: Extensive Red algaeDate: 9/28/02 Dive #: 781 Water temp. o F: 83 Location: Delray Ledge Observations: Filamentous red algae here.

_____________________________________________________________ ___________________________________
Date: 9/28/02 Dive #: 782 Water temp. o F: 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. o F: 82 L o c a t i o n : J e r r y ’ s N o - name north to Castle Ledge O b s e r v a t i o n s : R e d a l g a e e v e r y w h e r e , l e s s o n J e r r y ’ s ; C a s t l e L e d g e h e a v y .

________________ ________________________________________________________________________________
Date: 10/5/02 Dive #: 784 Water temp. o F: 82 Location: West edge of Table tops Observations: Very little red algae here.

________________________________________ ________________________________________________________
Date: 11/30/02 Dive #: 793 Water temp. o F: not recorded Location: Black Condo Observations: Red algae blankets everything.

__________________________________________________________________ ______________________________Date: 11/30/02 Dive #: 794 Water temp. o F: not recorded Location: West edge of Table tops Observations: Red algae in now here.

__________________________________________________________________________ ______________________

Date: 3/1/03 Dive #: 805 Water temp. o F: 69 Location: Casino Observations: No red algae here.

Date: 3/1/03 Dive #: 806 Water temp. o F: 70 Location: Horseshoe Observations: No red algae here.

Date: 3/8/03
D ive #: 807 Water temp. o F: 73 Location: Clubhouse south of Black Condo Observations: Little to no red algae.

________________________________________________________________________________________________ Date: 3/8/03 Dive #: 808 Water temp. o F : 74 Location: Table Tops to Briney Breezes Observations: Red algae present.Date: 3/16/03 Dive #: 809 Water temp. o F: 68 Location: Black Condo Observations: Red algae present.

_____________________________________________________ ___________________________________________

Date: 3/16/03 Dive #: 810 Water temp. o F: 68 Location: Inside west edge of Briney Breezes Observations: Red algae present.

Date: 4/26/03 Dive #: 825 Water temp. o F: 75 L o c a t i o n : L y

n n ’ s R e e f Observations: Red algae present.

Date: 7/12/03 Dive #: 849 Water temp. o F: 82 Location: Black Condo Observations: Red algae showing up here.

Date: 7/19/03 Dive #: 850 Water temp. o F: 77 Location: Casino Observations: No red algae pres ent.Date: 7/19/03 Dive #: 851 Water temp. o F: 82 Location: Horseshoe Observations: No red algae present.

________________________________________________________________________________________________ Date: 7/22/03 Dive #: 853
W ater temp. o F: 82 L o c a t i o n : B r i n e y B r e e z e s t o L y n n ’ s R e e f Observations: Red algae heavy and extensive.

Date: 7/23/03 Dive #: 854 Water temp. o F: 79 Location: Grouper Hole Observations: No red algae present.

Date: 8/9/03 Dive #: 860
Wa ter temp. o F: 84 L o c a t i o n : J e r r y ’ s N o - n a m e t o L y n n ’ s R e e f O b s e r v a t i o n s : R e d a l g a e p r e s e n t @ J e r r y ’ s i n c r e a s e s t o h e a v y a n d e x t e n s i v e @ L y n n ’ s .

Date: 8/24/03 Dive #: 863 Water temp. o F: 83 Location: Gulfstream Observations: Some red algae present, but not extensive.Date: 8/24/03 Dive #: 864 Water temp. o F: 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. o F: 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. o F: 82 Location: Clubhouse to Gulfsrtea m 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. o F: 81 Location: Delray Ledge Observations: Not a trace of Cyanobacteria.
Date: 9/20/03 Dive #: 869 Water temp. o F: 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 dive s 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 PHOTOGRAPHSPHOTO #1 L y n n ’ s R e e f (Prior to Cyanobacteria bloom)

photo by Sandra EdwardsPHOTOS #2 and #3 Cyanobacteria Gulf Stream Reef (September 2003)

photos by Ed Tiche norPHOTO #4 Cyanobacteria Gulf Stream Reef Outside Fingers (82 ft. below surface) Deep Water Sea Fan (September 2003)

photo by Ed TichenorPHOTO #5 Atlantic Spadefish L y n n ’ s R e e f ( No longer common on reef)

photo by Peter Schulz

## FIGURES