U.S. Department of the Interior

U.S. Geological Survey

Open-File Report 2016–1115

Seasonal Flux and Assemblage Composition of 

Planktic Foraminifera From the Northern Gulf of Mexico, 

2008–14

By Caitlin E. Reynolds and Julie N. Richey
U.S. Department of the Interior

SALLY JEWELL, Secretary

U.S. Geological Survey

Suzette M. Kimball, Director

U.S. Geological Survey, Reston, Virginia: 2016

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Suggested citation:

Reynolds, C.E., and Richey, J.N., 2016, Seasonal flux and assemblage composition of planktic foraminifera 

from the northern Gulf of Mexico, 2008–14: U.S. Geological Survey Open-File Report 2016–1115, 14 p., 

http://dx.doi.org/10.3133/ofr20161115. 

ISSN 2331-1258 (online)
iii

Contents

Abstract...........................................................................................................................................................1

Introduction.....................................................................................................................................................1

Regional Setting ............................................................................................................................................2

Materials and Methods.................................................................................................................................2

Results From 2013 ..........................................................................................................................................3

Results From 2014 ..........................................................................................................................................3

Discussion.......................................................................................................................................................3

Conclusions.....................................................................................................................................................3

Acknowledgments.........................................................................................................................................4

References Cited............................................................................................................................................4

Figures

1. Map showing location of the sediment-trap mooring in the northern

Gulf of Mexico at approximately 27.5° N. lat, 90.3° W. long ..................................................5

2. Graphs showing temperature/depth profiles of World Ocean Atlas 2009

climatology data, averaged monthly and conductivity-temperature-depth

casts for the sediment trap during 2008–14 .............................................................................6

3. Graphs showing salinity/depth profiles of World Ocean Atlas 2009 climatology

data, averaged monthly and conductivity-temperature-depth casts for the

sediment trap during 2008–14.....................................................................................................7

4. Graphs showing average daily flux of 7- to 14-day-long sampling intervals

of all planktic foraminifers and the 10 most abundant taxa during 2008–14.......................8

5. Graphs showing weekly relative abundance, in percent, of the 10 most

common taxa of planktic foraminifers during 2008–14.........................................................12

Table

[Available for download in Excel format from http://dx.doi.org/10.3133/ofr20161115]

1. Planktic foraminiferal flux and relative contribution in percent to the total 

assemblage for the 14 most common taxa, northern Gulf of Mexico
iv

Conversion Factors

International System of Units to Inch/Pound

Multiply By To obtain

Length

meter (m) 3.281 foot (ft) 

kilometer (km) 0.6214 mile (mi)

Area

square meter (m2

) 10.76 square foot (ft2)

Temperature in degrees Celsius (°C) may be converted to degrees Fahrenheit (°F) as

°F = (1.8 ×°C)+32.
Seasonal Flux and Assemblage Composition of 

Planktic Foraminifera From the Northern Gulf of Mexico, 

2008–14

By Caitlin E. Reynolds and Julie N. Richey

Abstract

The U.S. Geological Survey anchored a sediment trap in the northern Gulf of Mexico in January 2008 to 

collect seasonal time-series data on the flux and assemblage composition of live planktic foraminifers. This report 

provides an update of the previous time-series data to include continuous results from January 2013 through

May 2014. Ten taxa constituted ~95 percent of both the 2013 and 2014 assemblages: Globigerinoides 

ruber (pink and white varieties), Globigerinoides sacculifer, Globigerina calida, Globigerinella aequilateralis, 

Globorotalia menardii group [The Gt. menardii group includes Gt. menardii, Gt. tumida, and Gt. ungulata], 

Orbulina universa, Globorotalia truncatulinoides, Pulleniatina spp., and Neogloboquadrina dutertrei. In 2013, the 

mean daily flux was 177 tests per square meter per day (m–2 day–1), with maximum fluxes of >1,200 tests m–2 day–1

during the middle of February and minimum fluxes of <13 tests m–2 day–1 during the beginning of November. In 

2014, the mean daily flux was 189 tests m–2 day–1, with maximum fluxes of >900 tests m–2 day–1 at the end of January 

and minimum fluxes of <30 tests m–2 day–1 at the beginning of January. Globorotalia truncatulinoides showed a 

clear preference for the winter, consistent with data from 2008 to 2012. Globigerinoides ruber (white) flux data 

for 2012 (average 23 tests m–2 day–1) were consistent with data from 2011 (average 30 tests m–2 day–1) and 2010 

(average 29 tests m–2 day–1) and showed a steady threefold increase since 2009 (average 11 tests m–2 day–1) and a 

tenfold increase from the 2008 flux (3 tests m–2 day–1). The flux data from 2013 (average 15 tests m–2 day–1) and 2014 

(average 8 tests m–2 day–1) showed decline from the previous 3 years. 

Introduction 

A sediment trap was moored in the northern Gulf of Mexico in January 2008 as part of a U.S. Geological 

Survey Mendenhall Postdoctoral Fellowship project. The sediment trap, equipped with an automated sampling 

system, collected material in the water column from January 2008 to May 2014. In March 2015, the trap could not 

be recovered, and attempts to retrieve it were unsuccessful. A new sediment trap having the same specifications as 

the original trap was subsequently deployed and resumed collecting data in November 2015. Information on the 

trap, the trap mooring, planktic foraminifers as climate proxies, and the results from the first year (2008) are detailed 

in Tedesco and others (2009). In this report, we update results from the sediment-trap series to include material 

collected between January and December 2013 and between January and May 2014. This report presents the data 

without interpretation. For discussion and interpretation of flux data from 2008 to 2010, see Poore and others (2013). 
2 Seasonal Flux and Assemblage Composition of Planktic Foraminifera From the Northern Gulf of Mexico, 2008–14

Regional Setting 

The Gulf of Mexico is a semi-enclosed basin surrounded by the Gulf Coast of the United States, Mexico, and 

Cuba (fig. 1). Sea-surface temperature at the trap site ranges from a winter low of approximately 21 degrees Celsius 

(°C) to a summer high of 30 °C (World Ocean Atlas 2009 data cited in Locarnini and others, 2010). Sea-surface 

salinity ranges from about 35 practical salinity units (psu) in the winter to 32 psu in the summer (World Ocean Atlas 

2009 data cited in Antonov and others, 2010). 

The Gulf of Mexico is connected to the Caribbean Sea and tropical North Atlantic Ocean by the Loop Current. 

The Loop Current is a surface current that enters the Gulf of Mexico from the Caribbean Sea between Cuba and the 

Yucatan Peninsula and typically loops to the east and south before exiting through the Straits of Florida. 

The Gulf of Mexico, Caribbean Sea, and western tropical North Atlantic Ocean compose the Atlantic Warm 

Pool, the Atlantic portion of the Western Hemisphere Warm Pool (Wang and Enfield, 2001). The Atlantic Warm 

Pool is defined by the region of water warmer than 28.5 °C and constitutes a large part of the tropical heat engine, 

supplying moisture to the atmosphere and latent heat to North America from early spring to early fall (Wang and 

Enfield, 2001; Wang and others, 2006). World Ocean Atlas 2009 climatology data indicate the trap site is part of the 

Atlantic Warm Pool during the summer months of July, August, and September (Locarnini and others, 2010).

Materials and Methods

A McLane PARFLUX Mark 78 automated sediment trap was deployed in early January 2008 at approximately 

27.5o N. lat, 90.3o W. long, in about 1,150 meters (m) of water. The trap was positioned in the water column at a 

depth of 700 m on the mooring cable to guarantee the collection of deeper dwelling species of planktic foraminifers 

(for example, Globorotalia spp.). The trap was equipped with 21 collection cups mounted on a rotating plate that 

was programmed to rotate every 7 to 14 days (representing a 1- or 2-week collection period). From January 2008 to 

late May 2009, sample cups contained a buffered formalin solution made with seawater filtered at 0.44 micrometers 

(μm) and having an ambient salinity of approximently 33 psu. Since September 2009, sample cups have contained 

a density-gradient solution having a salinity of approximately 44 psu. Formalin (3.7 percent) and sodium borate 

were added to the density-gradient solution to poison and preserve the samples in all years of the study. The trap 

was recovered and redeployed every 3 months during 2008, and approximately every 6 to 9 months thereafter. 

A gap in sampling occurred between late May and late September 2009 and from the beginning of February 

to late March 2012 due to scheduling problems. Ten samples, one each from the weeks of March 17, April 7, 

May 5, October 22, November 19, and December 10, 2009; January 7, February 14, and February 24, 2010; and 

February 2013, were not recovered due to loss of the sampling cups during deployment and (or) recovery. The trap 

was lost at sea and became unrecoverable in March 2015, which represents the end of the data series presented in 

this report. A new sediment trap was deployed and resumed collecting samples in November 2015. During visits to 

the trap site, conductivity-temperature-depth (CTD) measurements (figs. 2 and 3) were collected using a Sea-Bird 

Electronics SBE9plus instrument. 

Sediment-trap samples were processed and analyzed at the Department of Earth and Ocean Sciences, University 

of South Carolina, Columbia, S.C., under a cooperative agreement with the U.S. Geological Survey. Samples were 

wet split into four aliquots using a precision rotary splitter, stored in buffered de-ionized water, and refrigerated. 

A quarter split was wet sieved over a 150-μm sieve and subsequently wet picked for all foraminifers. In samples 

containing fewer than 300 foraminifers in the first quarter split, an additional quarter split was processed and picked. 

The counts were then summed. All planktic foraminifers were identified to species. The species counts are reported 

as flux in tests per square meter per day (m–2 day–1). Flux was calculated by multiplying the individual species counts 

by number of splits, then dividing by the total duration of the sampling period, which was typically 7 or 14 days. 

Relative abundance (percentage of each species relative to the total number of individuals within each cup) is 
Discussion 3

reported weekly and for each season. Seasonal flux is the total flux for each individual species. Seasons are defined 

as winter (January, February, and March), spring (April, May, and June), summer (July, August, and September), 

and fall (October, November, and December). Relative seasonal abundances were calculated by dividing the total 

seasonal flux of each species by the total seasonal flux for all planktic foraminifers.

Results From 2013

From the sediment-trap material, 10 taxa of planktic foraminifers constituted ~95 percent of both the 2013 

and 2014 assemblage: Globigerinoides ruber (d’Orbigny) (pink and white varieties), Gs. sacculifer (Brady), 

Globigerina calida Parker, Globigerinella aequilateralis (Brady), Globorotalia menardii group [The Gt. menardii

group includes Gt. menardii (Parker, Jones, and Brady), Gt. tumida (Brady), and Gt. ungulata Bermudez], Orbulina universa d’Orbigny, Gt. truncatulinoides (d’Orbigny), Pulleniatina spp., and Neogloboquadrina dutertrei

(d’Orbigny) (table 1; figs. 4 and 5). 

The mean daily flux of planktic foraminifers recovered from the trap in 2013 was 177 tests m–2 day–1 (table 1; 

fig. 4). The winter flux composed ~67 percent of the annual flux and ranged from 108 to 1,244 tests m–2 day–1, 

with a mean flux of 409 tests m–2 day–1. The spring flux contributed ~13 percent of the annual flux and ranged from 

50 to 231 tests m–2 day–1, with a mean flux of 119 tests m–2 day–1. The summer flux contributed ~8 percent of the 

annual flux and ranged from 29 to 85 tests m–2 day–1, with a mean flux of 59 tests m–2 day–1. The fall flux contributed 

~12 percent of the annual flux and ranged from 12 to 189 tests m–2 day–1, with a mean flux of 75 tests m–2 day–1. 

Globorotalia truncatulinoides was the most abundant species in the winter season, composing ~33 percent of 

the assemblage during January‒March 2013 (fig. 5). The spinose species Globigerinoides ruber (pink) (10 percent), 

Globigerinoides ruber (white) (10 percent), Globigerinoides sacculifer (16 percent), and Globigerina calida

(28 percent), accounted for the bulk of the spring percentage (~64 percent combined). The summer season was 

dominated by the Globigerinoides genus (Gs. ruber (pink), Gs. ruber (white), and Gs. sacculifer), which made 

up ~66 percent of the total assemblage. Gs. ruber (pink) (10 percent), Gl. aequilateralis (9 percent), N. dutertrei

(21 percent), and Pulleniatina spp. (31 percent) accounted for ~71 percent of the fall assemblage. 

Results From 2014

The mean daily flux of planktic foraminifers recovered from the trap in 2014 was 189 tests m–2 day–1

(table 1; fig. 4). The winter flux contributed ~86 percent of the annual flux (January‒May) and ranged from 

29 to 970 tests m–2 day–1, with a mean flux of 222 tests m–2 day–1. Globorotalia truncatulinoides was again the most 

abundant species in the winter season, and composed ~54 percent of the assemblage during January‒March 2014 

(fig. 5). The spring (April and May only) flux contributed ~14 percent of the annual flux (January‒May) and ranged 

from 47 to 182 tests m–2 day–1, with a mean flux of 99 tests m–2 day–1.

Discussion

The sediment record has shown that Gs. ruber (white) is a major component (~20–30 percent) of the late 

Holocene planktic foraminifer assemblages (Kennett and others, 1985; LoDico and others, 2006; Poore and others, 

2011). However, in this study, Gs. ruber (white) has been anomalously low (1.5 percent (2008), ~5 percent (2009), 

~14 percent (2010, 2011, and 2012), ~8 percent (2013), and ~4 percent for the first five months of 2014). The 

addition of 2013‒2014 data to the 2008–12 flux (Reynolds and others, 2013) and percentage data provide for a 

better understanding of the inter-annual and intra-annual variability. A longer time series is needed to distinguish 

the natural range of all foraminiferal species.
4 Seasonal Flux and Assemblage Composition of Planktic Foraminifera From the Northern Gulf of Mexico, 2008–14

Conclusions

Sediment-trap data collected from January 2008 to May 2014 show that 10 taxa of planktic foraminifers 

composed ~93 percent of the total flux for the period. Globorotalia truncatulinoides flux data indicate that the 

species is present mostly during the winter months of January, February, and March. 

Acknowledgments

We thank Eric Tappa (University of South Carolina), Kaustubh Thirumalai (University of Texas), Joe Malbrough

(Louisiana Universities Marine Consortium), and the crew of the Louisiana Universities Marine Consortium research 

vessel Pelican for assistance in deploying and redeploying the sediment-trap mooring. 

References Cited 

Antonov, J.I., Seidov, D., Boyer, T.P., Locarnini, R.A., Mishonov, A.V., Garcia, H.E., Baranova, O.K., Zweng, M.M.,

and Johnson, D.R., 2010, World Ocean Atlas 2009, Volume 2: Salinity, in Levitus, S., ed., NOAA atlas 

NESDIS 69: Washington, D.C., U.S. Government Printing Office, 184 p. 

Kennett, J.P., Elmstrom, K., and Penrose, N.L., 1985, The last deglaciation in Orca Basin, Gulf of Mexico: Highresolution planktonic foraminifera changes: Palaeogeography, Paleoclimatology, Paleoecology, v. 50, p. 189–216.

Locarnini, R.A., Mishonov, A.V., Antonov, J.I., Boyer, T.P., Garcia, H.E., Baranova, O.K., Zweng, M.M., and

Johnson, D.R., 2010, World Ocean Atlas 2009, Volume 1: Temperature, in Levitus, S., ed., NOAA atlas

NESDIS 68: Washington, D.C., U.S. Government Printing Office, 184 p. 

LoDico, J.M., Flower, B.P., and Quinn, T.M., 2006, Subcentennial-scale climatic and hydrologic variability in the Gulf 

of Mexico during the early Holocene: Paleoceanography, v. 21, no. 3, http://dx.doi.org/10.1029/2005PA001243.

Poore, R.Z.; Tedesco, K.A., and Spear, J.W., 2013. Seasonal flux and assemblage composition of planktic foraminifers

from a sediment-trap study in the northern Gulf of Mexico, in Brock, J.C., Barras, J.A., and Williams, S.J., eds., 

Understanding and predicting change in the coastal ecosystems of the northern Gulf of Mexico: Journal of Coastal 

Research, Special Issue 63, p. 6‒19. 

Poore, R.Z., Verardo, S., Caplan, J., Pavich, K., and Quinn, T., 2011, Planktic foraminiferal relative abundance and 

trends in Gulf of Mexico Holocene sediments—Records of climate variability, in Buster, N.A., and Holmes, C.W., 

eds., Gulf of Mexico origin, waters, and biota; v. 3, Geology: Texas A&M University Press, p. 367‒379.

Reynolds, C.E., Richey, J.N., and Poore, R.Z., 2013, Seasonal flux and assemblage composition of planktic foraminifera from the northern Gulf of Mexico, 2008–2012: U.S. Geological Survey Open-File Report 2013–1243, 13 p., 

http://pubs.usgs.gov/of/2013/1243/. 

Tedesco, K.A., Spear, J.W., Tappa, Eric, and Poore, R.Z., 2009, Seasonal flux and assemblage composition of planktic foraminifera from the northern Gulf of Mexico: U.S. Geological Survey Open-File Report 2009–1293, 19 p.

Wang, Chunzai, and Enfield, D.B., 2001, The tropical Western Hemisphere Warm Pool: Geophysical Research Letters,

v. 28, no. 8, p. 1635–1638. 

Wang, Chunzai, Enfield, D.B., Lee, Sang-ki, and Landsea, C.W., 2006, Influences of the Atlantic Warm Pool on 

Western Hemisphere summer rainfall and Atlantic hurricanes: Journal of Climate, v. 19, p. 3011‒3028.

Figures
Figures 5

Figure 1. Location of the sediment-trap mooring (inverted yellow triangle) in the northern Gulf of Mexico at 

approximately 27.5° N. lat, 90.3° W. long.

100° W

30° N

25° N

95° W 90° W 85° W 80° W

UNITED STATES

MEXICO

Yucatan

Peninsula

CUBA

Caribbean Sea 

Straits of Florida 

0 100 200 300 400 KILOMETERS

0 100 200 MILES

Gulf of Mexico
6 Seasonal Flux and Assemblage Composition of Planktic Foraminifera From the Northern Gulf of Mexico, 2008–14

Figure 2. Temperature/depth profiles of World Ocean Atlas 2009 (WOA09) climatology data, averaged monthly (black lines) and 

conductivity-temperature-depth (CTD) casts for the sediment trap during 2008 (blue lines), 2009 (red lines), 2010 (green lines), 2011 

(brown lines), 2012 (purple lines), 2013 (orange lines), and 2014 (pink lines). WOA09 data are cited in Locarnini and others (2010). 

Abbreviations: m, meter; °C, degree Celsius.

0

100

200

300

400

500

600

700

800

900

1000

1100

1200

Depth (m)

4/20/08

Temperature ( ̊C)

4 8 12 16 20 24 28 32

1/7/08

1/8/09

1/20/11

3/9/10

3/27/12

WOA09 2008 2009 2010 2011 2012 2013 2014 

4 8 12 16 20 24 28 32 4 8 12 16 20 24 28 32

0

100

200

300

400

500

600

700

800

900

1000

1100

1200

Depth (m)

10/25/08 9/26/09

9/20/10 8/14/11

8/14/12

4 8 12 16 20 24 28 32 4 8 12 16 20 24 28 32 4 8 12 16 20 24 28 32

January March April

August September October

4 8 12 16 20 24 28 32

November

4 8 12 16 20 24 28 32

February

2/6/13

11/22/13

4 8 12 16 20 24 28 32

7/28/08

July

4 8 12 16 20 24 28 32 4 8 12 16 20 24 28 32

May June

4 8 12 16 20 24 28 32

December

06/02/14

400 
Figures 7

Figure 3. Salinity/depth profiles of World Ocean Atlas 2009 (WOA09) climatology data, averaged monthly (black lines) and 

conductivity-temperature-depth (CTD) casts for the sediment trap during 2008 (blue lines), 2009 (red lines), 2010 (green lines), 2011 

(brown lines), 2012 (purple lines), 2013 (orange lines), and 2014 (pink lines). WOA09 data are cited in Antonov and others (2010). 

Abbreviations: m, meter; psu, practical salinity unit.

0

100

200

300

400

500

600

700

800

900

1000

1100

1200 Depth (m)

Salinity (psu)

0

100

200

300

400

500

600

700

800

900

1000

1100

1200

Depth (m)

1/7/08

1/8/09

1/20/11

4/20/08

8/14/11 10/25/08

8/14/12

31 32 33 34 35 36 37

7/28/08

3/9/10

3/27/12

9/26/09

9/20/10

31 32 33 34 35 36 37 31 32 33 34 35 36 3731 32 33 34 35 36 37

31 32 33 34 35 36 37 31 32 33 34 35 36 3731 32 33 34 35 36 37

January March April

July August September October

31 32 33 34 35 36 37

February

31 32 33 34 35 36 37

November

11/22/13

2/6/13

31 32 33 34 35 36 3731 32 33 34 35 36 37

May June

31 32 33 34 35 36 37

December

WOA09 2008 2009 2010 2011 2012 2013 2014 

06/02/14

1200 
8 Seasonal Flux and Assemblage Composition of Planktic Foraminifera From the Northern Gulf of Mexico, 2008–14

Figure 4. Average daily flux of 7- to 14-day-long sampling intervals of all planktic foraminifers and the 

10 most abundant taxa during 2008–14. Note the scale change on the y-axis. Tick marks on the x-axis denote 

the first day of each month. Red bars indicate a gap in sampling from late May to late September 2009, from 

early February to late March 2012, and from June to December 2014. Red inverted triangles indicate the 

loss of ten sampling cups in 2009, 2010, and 2013. Abbreviation: m–2 day –1, per square meter per day.

0

40

0

40

80

120

0

40

80

0

40

80

Globigerinoides ruber (white) Globigerinoides sacculifer

0

40

80

120

0

40

No data No data

2008

2009

2010

2008

2009

2010

Flux (tests m-2 day-1 )

80

160

0

40

80

120

0

40

80

120

Globigerinoides ruber (pink)

0

40

80

120

No data

2008

2009

2010

160

0

40

80

120

160

0

40

80

120

160

0

40

80

120

0

40

80

120

0

40

80

120

0

40

80

120

2011 2011 2011

2012 2012 2012

160 160

200 200 200

240

0

40

80

2013

0

40

80

2013

0

40

80

120 2013

J F M A M J J A S O N D

0

40

2014

No data

J F M A M J J A S O N D

0

40

No data

2014

J F M A M J J A S O N D

0

40

No data

2014
Figures 9

Figure 4. Average daily flux of 7- to 14-day-long sampling intervals of all planktic foraminifers and the 

10 most abundant taxa during 2008–14. Note the scale change on the y-axis. Tick marks on the x-axis denote 

the first day of each month. Red bars indicate a gap in sampling from late May to late September 2009, from 

early February to late March 2012, and from June to December 2014. Red inverted triangles indicate the loss 

of ten sampling cups in 2009, 2010, and 2013. Abbreviation: m–2 day –1, per square meter per day.—Continued

0

200

400

0

40

80

120

0

100

200

300

0

200

400

600

0

40

80

120

0

100

0

40

80

No data No data No data

Globorotalia truncatulinoides Neogloboquadrina dutertrei Pulleniatina spp.

2008

2009

2010

2008

2009

2010

2008

2009

2010

0

200

400

600

600

400

200

0

200

400

600

2011

2012

0

200

0

40

80 2011

0

40 2012

0

100

2011

0

100

2012

0

100

200

Flux (tests m-2 day-1 )

0

200

400

600

2013

0

40

80

0

100

200

2013 2013

932

J F M A M J J A S O N D

0

200

400

600

2014

J F M A M J J A S O N D

0

40

80

0

100

200

2014

J F M A M J J A S O N D

2014

No data No data No data

609
10 Seasonal Flux and Assemblage Composition of Planktic Foraminifera From the Northern Gulf of Mexico, 2008–14

Figure 4. Average daily flux of 7- to 14-day-long sampling intervals of all planktic foraminifers 

and the 10 most abundant taxa during 2008–14. Note the scale change on the y-axis. Tick marks on 

the x-axis denote the first day of each month. Red bars indicate a gap in sampling from late May 

to late September 2009, from early February to late March 2012, and from June to December 2014. 

Red inverted triangles indicate the loss of ten sampling cups in 2009, 2010, and 2013. Abbreviation: 

m–2 day –1, per square meter per day.—Continued

Orbulina universa

2008

2009

2010

No data

2011

2012

0

40

80

120

0

40

80

0

40

80

No data

Others

2008

2009

2010

0

40

80

2011

0

40

80 2012

0

200

400

600

800 2008

0

200

400

600 2009

800

1000

0

200

400

600 2010

800

0

200

400

600 2011

800

0

200

400

600

2012

No data

0

20

40

60

0

20

40

0

20

0

20

40

0

20

40

Total foraminifers

120

120

296

Flux (tests m-2 day-1 )

2013

0

20

40

0

200

400

600 2013

800

1000

0

40

2013

1244

J F M A M J J A S O N D

2014

0

20

J F M A M J J A S O N D

0

40

2014

No data No data 0

200

400

600

800

1000

2014

J F M A M J J A S O N D

No data
Figures 11

Figure 4. Average daily flux of 7- to 14-day-long sampling intervals of all planktic foraminifers and the 10 most 

abundant taxa during 2008–14. Note the scale change on the y-axis. Tick marks on the x-axis denote the first day 

of each month. Red bars indicate a gap in sampling from late May to late September 2009, from early February to 

late March 2012, and from June to December 2014. Red inverted triangles indicate the loss of ten sampling cups 

in 2009, 2010, and 2013. Abbreviation: m–2 day –1, per square meter per day.—Continued

0

40

0

40

80

0 0

40

80

120

Globorotalia menardii group Globigerina calida Globigerinella aequilateralis

2008

2009

2010

2008

2009

2010

2008

2009

2010

No data No data

80

0

40

80

120

0

40

80

120

40

80

120

0

40

80

120

0

40

2011 2011 2011

0

40

2012 2012 2012

0

40

80

120

0

No data 0

40

80

120

40

0

40

80

0

40

80

0

40

80

187

276

Flux (tests m-2 day-1 )

0

40

2013 2013 2013

0

40

80

120

0

40

80

150

J F M A M J J A S O N D J F M A M J J A S O N D J F M A M J J A S O N D

0

40

2014 2014 2014

0

40

80

120

0

40

No data No data No data
12 Seasonal Flux and Assemblage Composition of Planktic Foraminifera From the Northern Gulf of Mexico, 2008–14

Figure 5. Weekly relative abundance, in percent (%), of the 10 most common taxa of planktic foraminifers 

during 2008–14. Note the scale change on the y-axis. Tick marks on the x-axis denote the first day of each 

month. Red bars indicate a gap in sampling from late May to late September 2009, from early February to late 

March 2012, and from June to December 2014. Red inverted triangles indicate the loss of ten sampling cups 

in 2009, 2010, and 2013. 

% Abundance

Globigerinoides ruber (pink) Globigerinoides sacculifer

No data No data

2008

2009

2010

2008

2009

2010

0

20

40

60

0

20

40

0

20

40

60

0

20

40

0

20

40

0

20

40

Globigerinoides ruber (white)

No data

2008

2009

0

20

40

0

20

40

0

20

0

20

40

60

0

20

40

0

20

40

0

20

40

60

0

20

40

60

0

20

40

2011 2011 2011

2012 2012 2012

2010

0

20

40

0

20

40

60

0

20

40 2013 2013 2013

No data

J F M A M J J A S O N D J F M A M J J A S O N D J F M A M J J A S O N D

0

20

40

0

20

40

0

20

2014 2014 2014

No data No data
Figures 13

Figure 5. Weekly relative abundance, in percent (%), of the 10 most common taxa of planktic foraminifers 

during 2008–14. Note the scale change on the y-axis. Tick marks on the x-axis denote the first day of each 

month. Red bars indicate a gap in sampling from late May to late September 2009, from early February to 

late March 2012, and from June to December 2014. Red inverted triangles indicate the loss of ten sampling 

cups in 2009, 2010, and 2013.—Continued

Globorotalia menardii group Globigerina calida Globigerinella aequilateralis

% Abundance

No data No data

2008

2009

2010

2008

2009

2010

0

20

40

0

20

40

0

20

40

60

0

20

40

0

20

40

0

20

No data

2008

2009

0

20

40

0

20

40

0

20

60

0

20

40

0

20

0

20

40

60

0

20

40

0

20

40

0

20

40

2011 2011 2011

2012 2012 2012

40

60

2010

Orbulina universa Others

No data

2008

2009

2010

0

20

40

60

0

20

40

0

20

40

60

0

20

40

0

20

40

2011

2012

No data

2008

2009

2010

0

20

40

0

20

40

0

20

0

20

0

20

2011

2012

0

20

0

20

40

0

20

2013 2013 40 2013

0

20

40 2013

0

20

2013

J F M A M J J A S O N D J F M A M J J A S O N D J F M A M J J A S O N D

0

20

0

20

40

0

20

2014 2014 40 2014

No data No data No data

J F M A M J J A S O N D

0

20

40 2014

J F M A M J J A S O N D

0

20

2014

No data No data
14 Seasonal Flux and Assemblage Composition of Planktic Foraminifera From the Northern Gulf of Mexico, 2008–14

Figure 5. Weekly relative abundance, in percent (%), of the 10 most common taxa of planktic foraminifers 

during 2008–14. Note the scale change on the y-axis. Tick marks on the x-axis denote the first day of each 

month. Red bars indicate a gap in sampling from late May to late September 2009, from early February to 

late March 2012, and from June to December 2014. Red inverted triangles indicate the loss of ten sampling 

cups in 2009, 2010, and 2013.—Continued

No data No data No data

Globorotalia truncatulinoides Neogloboquadrina dutertrei Pulleniatina spp.

2008

2009

2010

2008

2009

2010

2008

2009

2010

0

20

40

60

80

0

20

40

60

0

20

40

60

80

0

20

40

0

20

40

0

20

0

20

40

0

20

40

0

20

40

60

% Abundance

80

100

40

60 60

2011

0

20

40

60

80

100

2012

0

20

40

60

2011

0

20

40

2012

0

20

2011

0

20

40

2012

0

20

40 40

J F M A M J J A S O N D J F M A M J J A S O N D J F M A M J J A S O N D

2013

0

20

40

60

2014

0

20

40

60

2013

0

20

40

2014

0

20

2013

0

20

40

2014

0

20

40 40

No data No data No data

60

80

ISSN 2331-1258 (online)

http://dx.doi.org/10.3133/ofr20161115