Dr. Hans Paerl: hpaerl@email.unc.edu

Dr. Valerie Paul: Paul@si.edu

Dr. Judith M. O’Neil: joneil@hpl.umces.edu

PRINCIPAL 

INVESTIGATORS:

http://www.umces.edu

Printed on 100% recycled paper

 The genus Lyngbya includes prolific producers 

of secondary metabolites, with over 200 

compounds isolated from these cyanobacteria 

worldwide. Because these compounds often make 

cyanobacteria unpalatable to consumers, they 

are able to bloom under conditions of appropriate 

temperature, light, and nutrient availability. L. 

polychroa strains produce microcolins a and b, 

and when nutrients are replete, L. polychroa

demonstrates a trade-off between secondary 

metabolite production and growth. At Sanibel, L. 

majuscula contained malyngolide- the first report of 

this toxic compound in Florida waters. When N, P, 

and chelated iron were added to growth chambers, 

L. majuscula was found to produce more malyngolide 

than in control treatments.

 Enrichment of nitrogen, phosphorus, and iron 

can lead to increased growth, productivity, and 

changes in secondary metabolite concentration 

among different Lyngbya species. Since many of 

the secondary metabolites produced by Lyngbya

can act as feeding deterrents to generalist grazers, 

these compounds may give Lyngbya a competitive 

advantage over other benthic algae. Subsequent 

blooms may inhibit the feeding of benthic grazers.

 The present study confirms and extends the 

results from other coastal studies, which indicate 

that both N and P inputs need to be controlled when 

non-N-fixing HABs co-occur (such as the red tide 

organism Karenia) with N-fixing cyanobacterial 

species. Therefore, we can conclude that single 

nutrient input controls are ineffective in addressing 

HAB ramifications. A larger-scale vision of both 

the ecosystems and the ecophysiology of these 

HABs is essential for setting thresholds for nutrient 

management strategies. Additionally, these results 

add to the growing body of knowledge that indicates 

the introduction of nutrients into the marine 

environment can not only increase the prevalence 

of HABs, but may also facilitate greater secondary 

metabolite production.

O

O OH

Malyngolide

References:

Arthur, K.E., V.J. Paul, H.W. Paerl, J. M O’Neil, J. Joyner, and T. Meickle. (In press). Nutrient enrichment of the cyanobacterium Lyngbya spp.: Effect on growth, secondary metabolite 

 concentration, and feeding by the specialist grazer Stylocheilus striatus. Mar. Ecol. Prog. Ser.

Arthur, K.E., K. Semon, A. Capper, C. Ross, A.A. Erickson, S. Gunasekara, T. Meickle, S. Reed, J. Kwan, S. Matthew, H. Luesch, and V.J. Paul. (submitted) Distribution and chemical ecology 

 of Lyngbya spp. (Cyanobacteria) in Florida, USA. Harmful Algae.

Paerl, H.W., J.J. Joyner, A.R. Joyner, K. Arthur, V.J. Paul, J.M. O’Neil, amd C.A. Heil. 2008. Co-occurrence of dinoflagellates and cyanobacteria harmful algal blooms in southwest Florida 

 coastal waters: A case for dual nutrient (N and P) input controls. Mar. Ecol. Prog. Ser. 371: 143-153.

Sharp, L., K.E. Arthur, L. Gu, D. Sherman, C. Ross, G. Harrison, T. Meickle, H. Luesch, S. Matthew, and V.J. Paul. 2009. Phylogenetic and chemical diversity of three chemotypes of bloom-

 forming Lyngbya species (Cyanobacteria: Oscillatoriales) from reefs of Southeastern Florida. Appl. Environ.Microbiol. 75: 2879-2888. Malyngolide (mg.g-1dry wt Lyngbya)

ANOVA: F = 5.096 

df = 7 

p < 0.001 

0.0 

0.5 

1.0 

1.5 

2.0 

2.5 

Control +N +P +N&P +Fe +EDTA +Fe EDTA +All 

a

ab

a

a

ab ab ab

b

Treatment

Malyngolide concentrations in treatment groups at the end 

of the 2007 5-day bioassay from L. majuscula, showing the 

cumulative effects of N, P, Fe, and EDTA.

www.johnsabia.com

Continued 

development 

along both sides 

of Florida’s coast 

continues to 

present nutrient 

management 

issues, which 

will affect future 

Lyngbya blooms. 

Researchers: Dr. Jennifer Joyner, Dr. Karen Arthur, Alan Joyner, Dr. Angela Capper, Dr. Cliff 

Ross, and Dr. Cynthia Heil

Graphics, design and layout by Judith M. O’Neil, Kris Beckert, and Alan Joyner

Acknowledgements: Sanibel-Captiva Consevation Marine Laboratory, Dr. Richard Bartleson, Nova Southeastern University Oceanographic Center, 

Dr. Richard E. Dodge, and Broward County Environmental Protection & Growth Management Department, Ken Banks

Based on NOAA ECOHAB research grant #NA05NOS4781194
Right: Lyngbya overgrowing seagrass.

Below: Primary productivity 

represented as 12C uptake in L. 

majuscula bioassay at T0, T2, and T4

(96 h incubation) after daily additions 

of N, P, Fe, EDTA and combinations of 

nutrients. Error bars represent + 1 SE 

(n = 5)

 Blooms of the species Lyngbya majuscula

have been occurring on the seagrass beds and 

sediments of Florida’s Gulf Coastal region of 

Sanibel Island. These blooms can overgrow 

seagrass, potentially smothering other benthic 

organisms. Mangroves in this region are also 

adversely affected by Lyngbya. Results of 

the bioassay conducted in this study showed 

increased primary production with additions of 

N and P. Although L. majuscula is primarily a 

benthic species, the oxygen it produces by rapid 

photosynthesis can get trapped in the filaments, 

causing tufts to become buoyant. The tufts can 

dislodge from the bottom, float up to the surface 

of the water, and form rafts of material that 

washes up on beaches. This material-in addition 

to being unsightly-is malodorous as it rots and 

can maintain toxic properties deleterious to 

humans and animals even after drying.

Lyngbya has the ability to use 

atmospheric nitrogen (N2

) for its cellular 

needs through the process of N-fixation, 

an energetically demanding process that 

requires high amounts of iron for the enzyme 

nitrogenase that mediates the process. 

Experiments from Sanibel indicate that 

bioavailable iron stimulates L. majuscula

productivity and N-fixation. In addition 

to N-fixation, L. majuscula can also take 

up inorganic forms of nitrogen, such as 

ammonium, nitrate, and the organic form urea.

0

5

10

15

20

25

30

35

40

0.05 0.1 0.5 1

N concentration (μg atm N)

Uptake (V x 1000h-1)

NH4

L. majuscula

NO3

Urea

Florida’s Gulf Coastal region of Sanibel Island is being affected by blooms of the cyanobacteria Lyngbya majuscula , which fouls 

beaches and cause the death of seagrasses . These blooms are most likely due to nutrient inputs from development 

recreational activities , and groundwater . Study sites in 2006 and in 2007 revealed that both N and P and iron are 

essential in bloom formation, due to this species’ ability to fix and utilize atmospheric N. 

X

Fe

Fe

0

50

100

150

200

250

Control +N +P +N&P +Fe +EDTA +FeEDTA +All

C uptake (g dry weight-1 h-1)

Lyngbya majuscula

Treatment

T2

T4
Right: Lyngbya overgrowing seagrass.

Below: Primary productivity 

represented as 12C uptake in L. 

majuscula bioassay at T0, T2, and T4

(96 h incubation) after daily additions 

of N, P, Fe, EDTA and combinations of 

nutrients. Error bars represent + 1 SE 

(n = 5)

 Blooms of the species Lyngbya majuscula

have been occurring on the seagrass beds and 

sediments of Florida’s Gulf Coastal region of 

Sanibel Island. These blooms can overgrow 

seagrass, potentially smothering other benthic 

organisms. Mangroves in this region are also 

adversely affected by Lyngbya. Results of 

the bioassay conducted in this study showed 

increased primary production with additions of 

N and P. Although L. majuscula is primarily a 

benthic species, the oxygen it produces by rapid 

photosynthesis can get trapped in the filaments, 

causing tufts to become buoyant. The tufts can 

dislodge from the bottom, float up to the surface 

of the water, and form rafts of material that 

washes up on beaches. This material-in addition 

to being unsightly-is malodorous as it rots and 

can maintain toxic properties deleterious to 

humans and animals even after drying.

Lyngbya has the ability to use 

atmospheric nitrogen (N2

) for its cellular 

needs through the process of N-fixation, 

an energetically demanding process that 

requires high amounts of iron for the enzyme 

nitrogenase that mediates the process. 

Experiments from Sanibel indicate that 

bioavailable iron stimulates L. majuscula

productivity and N-fixation. In addition 

to N-fixation, L. majuscula can also take 

up inorganic forms of nitrogen, such as 

ammonium, nitrate, and the organic form urea.

0

5

10

15

20

25

30

35

40

0.05 0.1 0.5 1

N concentration (μg atm N)

Uptake (V x 1000h-1)

NH4

L. majuscula

NO3

Urea

Florida’s Gulf Coastal region of Sanibel Island is being affected by blooms of the cyanobacteria Lyngbya majuscula , which fouls 

beaches and cause the death of seagrasses . These blooms are most likely due to nutrient inputs from development 

recreational activities , and groundwater . Study sites in 2006 and in 2007 revealed that both N and P and iron are 

essential in bloom formation, due to this species’ ability to fix and utilize atmospheric N. 

X

Fe

Fe

0

50

100

150

200

250

Control +N +P +N&P +Fe +EDTA +FeEDTA +All

C uptake (g dry weight-1 h-1)

Lyngbya majuscula

Treatment

T2

T4
Dr. Hans Paerl: hpaerl@email.unc.edu

Dr. Valerie Paul: Paul@si.edu

Dr. Judith M. O’Neil: joneil@hpl.umces.edu

PRINCIPAL 

INVESTIGATORS:

http://www.umces.edu

Printed on 100% recycled paper

 The genus Lyngbya includes prolific producers 

of secondary metabolites, with over 200 

compounds isolated from these cyanobacteria 

worldwide. Because these compounds often make 

cyanobacteria unpalatable to consumers, they 

are able to bloom under conditions of appropriate 

temperature, light, and nutrient availability. L. 

polychroa strains produce microcolins a and b, 

and when nutrients are replete, L. polychroa

demonstrates a trade-off between secondary 

metabolite production and growth. At Sanibel, L. 

majuscula contained malyngolide- the first report of 

this toxic compound in Florida waters. When N, P, 

and chelated iron were added to growth chambers, 

L. majuscula was found to produce more malyngolide 

than in control treatments.

 Enrichment of nitrogen, phosphorus, and iron 

can lead to increased growth, productivity, and 

changes in secondary metabolite concentration 

among different Lyngbya species. Since many of 

the secondary metabolites produced by Lyngbya

can act as feeding deterrents to generalist grazers, 

these compounds may give Lyngbya a competitive 

advantage over other benthic algae. Subsequent 

blooms may inhibit the feeding of benthic grazers.

 The present study confirms and extends the 

results from other coastal studies, which indicate 

that both N and P inputs need to be controlled when 

non-N-fixing HABs co-occur (such as the red tide 

organism Karenia) with N-fixing cyanobacterial 

species. Therefore, we can conclude that single 

nutrient input controls are ineffective in addressing 

HAB ramifications. A larger-scale vision of both 

the ecosystems and the ecophysiology of these 

HABs is essential for setting thresholds for nutrient 

management strategies. Additionally, these results 

add to the growing body of knowledge that indicates 

the introduction of nutrients into the marine 

environment can not only increase the prevalence 

of HABs, but may also facilitate greater secondary 

metabolite production.

O

O OH

Malyngolide

References:

Arthur, K.E., V.J. Paul, H.W. Paerl, J. M O’Neil, J. Joyner, and T. Meickle. (In press). Nutrient enrichment of the cyanobacterium Lyngbya spp.: Effect on growth, secondary metabolite 

 concentration, and feeding by the specialist grazer Stylocheilus striatus. Mar. Ecol. Prog. Ser.

Arthur, K.E., K. Semon, A. Capper, C. Ross, A.A. Erickson, S. Gunasekara, T. Meickle, S. Reed, J. Kwan, S. Matthew, H. Luesch, and V.J. Paul. (submitted) Distribution and chemical ecology 

 of Lyngbya spp. (Cyanobacteria) in Florida, USA. Harmful Algae.

Paerl, H.W., J.J. Joyner, A.R. Joyner, K. Arthur, V.J. Paul, J.M. O’Neil, amd C.A. Heil. 2008. Co-occurrence of dinoflagellates and cyanobacteria harmful algal blooms in southwest Florida 

 coastal waters: A case for dual nutrient (N and P) input controls. Mar. Ecol. Prog. Ser. 371: 143-153.

Sharp, L., K.E. Arthur, L. Gu, D. Sherman, C. Ross, G. Harrison, T. Meickle, H. Luesch, S. Matthew, and V.J. Paul. 2009. Phylogenetic and chemical diversity of three chemotypes of bloom-

 forming Lyngbya species (Cyanobacteria: Oscillatoriales) from reefs of Southeastern Florida. Appl. Environ.Microbiol. 75: 2879-2888. Malyngolide (mg.g-1dry wt Lyngbya)

ANOVA: F = 5.096 

df = 7 

p < 0.001 

0.0 

0.5 

1.0 

1.5 

2.0 

2.5 

Control +N +P +N&P +Fe +EDTA +Fe EDTA +All 

a

ab

a

a

ab ab ab

b

Treatment

Malyngolide concentrations in treatment groups at the end 

of the 2007 5-day bioassay from L. majuscula, showing the 

cumulative effects of N, P, Fe, and EDTA.

www.johnsabia.com

Continued 

development 

along both sides 

of Florida’s coast 

continues to 

present nutrient 

management 

issues, which 

will affect future 

Lyngbya blooms. 

Researchers: Dr. Jennifer Joyner, Dr. Karen Arthur, Alan Joyner, Dr. Angela Capper, Dr. Cliff 

Ross, and Dr. Cynthia Heil

Graphics, design and layout by Judith M. O’Neil, Kris Beckert, and Alan Joyner

Acknowledgements: Sanibel-Captiva Consevation Marine Laboratory, Dr. Richard Bartleson, Nova Southeastern University Oceanographic Center, 

Dr. Richard E. Dodge, and Broward County Environmental Protection & Growth Management Department, Ken Banks

Based on NOAA ECOHAB research grant #NA05NOS4781194