Ann Bucklin

University of Connecticut Department of Marine Sciences
1080 Shennecossett Road Groton, CT 06340
Phone: (860) 405-9260
Fax: (860) 405-9153

My research focus is the molecular ecology and evolution of zooplankton. My laboratory group uses diverse molecular approaches to study population ecology, , population genetics, phylogeography, species diversity, and evolution of marine holozooplankton, especially copepods and euphausiids. 

Environmental Transcriptomics: We use genomic and transcriptomic approaches to examine gene expression profiles in zooplankton using RNA sequencing, quantitative real-time PCR (QPCR) of target genes, and DNA microarrays. Current focus includes the copepod Calanus finmarchicus in the North Atlantic and the salp Salpa thompsoni in the Southern Ocean.  For more about our studies on the Southern Ocean salp and Antarctic krill studies, see 

Population Genetics / Phylogeography: We are using various genetic markers - including multigene sequences, Single Nucleotide Polymorphisms (SNPs), and Restriction-site Associated DNA (RAD) markers - to examine spatial patterns of genetic variation of zooplankton from small-scale patches to ocean-basin scale gyres, and to measure population connectivity and infer pathways of transport in ocean currents. 

Species biodiversity: We have worked to develop a new global view of zooplankton species diversity through the Census of Marine Zooplankton (CMarZ, see, an ocean realm field project of the Census of Marine Life (CoML).  We used DNA sequences for mitochondrial cytochrome oxidase I as barcodes (i.e., short DNA sequences for species recognition and discrimination) to characterize global-scale patterns of zooplankton species distribution and diversity. We are continuing this research focus using NGS amplicon sequencing of environmental samples to allow rapid analysis of species diversity and population connectivity.

Phylogeny: We are using multigene datasets to analyze the evolutionary history and molecular phylogeny of copepods and euphausiids. A particular goal is to integrate molecular and morphological phylogenies for improved understanding of the timing and mode of speciation of these ecologically important and taxonomically complex zooplankton groups.

My laboratory group currently includes:

   - Martha J. Hauff (Postdoctoral Fellow)

   - Ebru Unal (MSTC Assist. Res. Scientist and Assistant Scientist, Mystic Aquarium)

   - Paola Batta-Lona (MSTC Assist. Res. Scientist and CONICET Postdoctoral Fellow, CICESE, Mexico)

   - Kayla Erikson (MS Student)



Research Projects

Environmental Genomics of Salpa thompsoni in the Southern Ocean - National Science Foundation / Office of Polar Programs

Climate forcing of Calanus finmarchicus populations of the North Atlantic. - National Science Foundation / U.S. GLOBEC Synthesis

Trophic Structure and Interactions of the Pelagic Nekton Assemblage - National Science Foundation / Biological Oceanography

Oceanography Students

Kayla Erikson - M.Sc. Student

Oceanography Alumni

Paola Batta Lona - Ph.D. 2014
Brian Ortman - Ph.D. 2008
Ebru Unal - Ph.D. 2011

Honors Received

Fulbright Senior Fellowship, Institute of Marine Research, Bergen, Norway (1993-1994)

Fellow of the American Association for the Advancement of Science (Elected 1995)

Member, Connecticut Academy of Science and Engineering (Elected 2006)



For reference and citation information, see my Google Scholar Profile at:


Snelgrove, P., E. Vanden Berghe, P. Miloslavich, N. Bailly, A. Brandt, A. Bucklin, and 18 others (In review) Gradients in marine biodiversity. Chapter 35 In: United Nations World Ocean Assessment I.  See

Viñas, M.D., L. Blanco-Bercial, A. Bucklin, H. Verheye, J. Guilherme, F. Bersano and S. Ceballos, 2015. Phylogeography of the copepod Calanoides carinatus s.l. (Krøyer) reveals cryptic species and delimits C. carinatus s.s. distribution in SW Atlantic Ocean. J. Exp. Mar. Biol. Ecol. 468: 97-104

Wiebe, P.H., M. Benfield and A. Bucklin (In review) Zooplankton sample collection, preservation, and analysis. In: The Plankton Handbook, C. Castellani and M. Edwards [Eds.] Oxford University Press


Aarbakke, O.N., A. Bucklin, C. Halsband, and F. Norrbin. 2014. Comparative phylogeography and demographic history of five sibling species of Pseudocalanus (Copepoda: Calanoida) in the North Atlantic Ocean. J. Exp. Mar. Biol. Ecol. 461: 479-488

Blanco-Bercial, L., A. Cornils, N.J. Copley, and A. Bucklin. 2014. DNA barcoding of marine copepods: assessment of analytical approaches to species identification. PLOS-Currents Tree of Life [2014 June 23]


Christie, A.E., V. Roncalli, P. Batta-Lona, M.D. McCoole, B.L. King, A. Bucklin, D.K. Hartline, and P.H. Lenz. 2013. In silico characterization of the insect diapause-associated protein couch potato (CPO) in Calanus finmarchicus (Crustacea: Copepoda). Comp. Biochem. Physiol. Part D 8: 45–57.

Unal, E., A. Bucklin, P.H. Lenz, and D.W. Towle (2013) Gene expression of the marine copepod Calanus finmarchicus: Responses to small-scale environmental variation in the Gulf of Maine (NW Atlantic Ocean). J. exp. Mar. Biol. Ecol. 446:76-85.


Cepeda, G.D., L. Blanco-Bercial, A. Bucklin, C.M. Berón, M.D. Viñas. 2012. Molecular taxonomic analysis of three species of Oithona (Copepoda, Cyclopoida) from the Argentine sector of the South Atlantic Ocean: comparative analysis using 28S rDNA. PLoS-One 7 (4): e35861

Kozol, R., L. Blanco-Bercial, and A. Bucklin. 2012. Lack of genetic divergence between Calanus agulhensis and C. sinicus (Copepoda; Calanoida). PLoS-One 7(10): e45710. doi:10.1371/journal.pone.0045710

Lenz, P.H., E. Unal, R.P. Hassett, C.M. Smith, A. Bucklin, A.E. Christie, and D.W. Towle. 2012. Functional genomics resources for the North Atlantic copepod, Calanus finmarchicus: EST database and physiological microarray. Comp. Biochem. Physiol. Part D, 7: 110–123



Aarbakke, O.N.S., A. Bucklin, C. Halsband-Lenk, and M.F. Norrbin. 2011. Discovery of Pseudocalanus moultoni Frost 1989 in Northeast Atlantic waters based on mitochondrial COI sequence variation. J. Plankton Res.  33:1487-1495 [doi: 10.1093/plankt/fbr057]

Batta-Lona, P.G., A. Bucklin, T. Patarnello, N.J. Copley, and P.H. Wiebe, 2011. Population genetic variation of the southern ocean krill, Euphausia superba, in the western Antarctic Peninsula region using Single Nucleotide Polymorphisms (SNPs).  Deep-Sea Res. II 58:1652-1661 [ doi:10.1016/j.dsr2.2010.11.017 ]

Blanco-Bercial, L. F. álvarez-Marqués, and A. Bucklin. 2011. Comparative phylogeography and connectivity of sibling species of the marine copepod Clausocalanus (Calanoida). J. Exp. Mar. Biol. Ecol. 404: 108-115 [ doi:10.1016/j.jembe.2011.05.011 ]

Blanco-Bercial, L., J. Bradford-Grieve, and A.Bucklin. 2011. Molecular phylogeny of Calanoida (Copepoda). Mol. Phylogen. Evol. 59:103–113 [ ]

Bortolotto, E., A. Bucklin, M. Mazzavilaa, L. Zane, and T. Patarnello. 2011. Gone with the currents: lack of genetic differentiation at the circum-continental scale in the Antarctic krill Euphausia superba. BMC – Genetics 12: 32 [ doi:10.1186/1471-2156-12-32 ]

Bucklin, A., D. Steinke, and L. Blanco-Bercial, 2011. DNA barcoding of marine metazoa. Annual Review of Marine Science 2011, Vol. 3: 471–508  [ doi:10.1146/annurev-marine-120308-080950 ]

Govindarajan, A.F., A. Bucklin, and L.P. Madin. 2011. A molecular phylogeny of the Thaliacea. J. Plankton Res. 33:843-853 [ doi:10.1093/plankt/fbq157 ]



Bucklin, A., R.R.Hopcroft, K.N. Kosobokova, L.M. Nigro, B.D. Ortman, R.M. Jennings, and C.J. Sweetman. 2010. DNA barcoding of Arctic Ocean holozooplankton for species identification and recognition.  Deep-Sea Res. II 57:40-48

Bucklin, A., S. Nishida, S. Schnack-Schiel, P.H. Wiebe, D. Lindsay, R.J. Machida, and N.J. Copley. 2010. Chapter 13. A Census of Zooplankton of the Global Ocean, In: Marine Life: Diversity, Distribution, and Abundance. A. McIntyre [Ed.], Wiley-Blackwell, Oxford.  Pp. 247-265

Bucklin, A., B.D. Ortman, R.M. Jennings, L. Nigro, C.J. Sweetman, N.J. Copley, and P.H. Wiebe. 2010. A “Rosetta Stone” for zooplankton: DNA barcode analysis of holozooplankton diversity of the Sargasso Sea (NW Atlantic Ocean). Deep-Sea Res. II 57:2234-2247

Grabbert, S., J. Renz, H.-J. Hirche, and A. Bucklin. 2010. Species-specific PCR (SS-PCR) discrimination of species of the calanoid copepod Pseudocalanus, P. acuspes and P. elongatus, in the Baltic and North Seas. Hydrobiologia 652:289-297

Jennings, R.M., A. Bucklin, H. Ossenbrügger, and R.R. Hopcroft. 2010. Analysis of genetic diversity of planktonic gastropods from several ocean regions using DNA barcodes. Deep-Sea Research II 57:2199-2210

Jennings, R.M., A. Bucklin, and A.C. Pierrot-Bults. 2010. Barcoding of arrow worms (Phylum Chaetognatha) from three oceans: genetic diversity and evolution within an enigmatic phylum. PLoS-ONE [doi:10.1371/journal.pone.0009949]

Ortman, B. D., A. Bucklin, F. Pages, and M. Youngbluth. 2010. DNA barcoding of the Medusozoa. Deep-Sea Res. II 57:2148-2156

Sutton, T.T., P.H. Wiebe, L.P. Madin and A. Bucklin. 2010. Diversity and community structure of pelagic fishes to 5000 m depth in the Sargasso Sea. Deep-Sea Res. II 57:2220-2233

Unal, E. and A. Bucklin. 2010. Basin-scale population genetic structure of the planktonic copepod Calanus finmarchicus in the North Atlantic Ocean. Prog. Oceanogr. 87:175-186

Wiebe, P.H., A. Bucklin, L.P. Madin, M.V. Angel, T. Sutton, F. Pagés, R.R. Hopcroft, and D. Lindsay. 2010. Deep-sea holozooplankton species diversity in the Sargasso Sea, Northwestern Atlantic Ocean. Deep-Sea Res. II 57:2157-2166


Bucklin, A. and B.W. Frost. 2009. Morphological and molecular phylogenetic analysis of evolutionary lineages within Clausocalanus (Crustacea, Copepoda, Calanoida). J. Crust. Biol. 29: 111-120



Bucklin, A., P.H. Wiebe, S.B. Smolenack, N.J. Copley, J.G. Beaudet, K.G. Bonner, J. Färber Lorda, and J.J. Pierson. 2007. DNA barcodes for species identification of euphausiids (Euphausiacea, Crustacea).  J. Plankton Res. 29:483-493


Ueda H. and A. Bucklin. 2006. Acartia (Odontacartia) ohtsukai, a newbrackish-water calanoid copepod from Ariake Bay, Japan, with a redescription of the closely related A. pacifica from the Seto Inland Sea.  Hydrobiologia 500:77-91



Manning, C.A. and A. Bucklin. 2005. Multivariate analysis of the copepod community of near-shore waters in the western Gulf of Maine (Northwest Atlantic). Mar. Ecol. Progr. Ser. 292:233-249

Papetti, C., L. Zane, E. Bortolotto, A. Bucklin, and T. Patarnello. 2005. Genetic differentiation and local temporal stability of population structure in the euphausiid Meganyctiphanes norvegica. Mar. Ecol. Progr. Ser. 289:225-235 



Bucklin, A. and L.D. Allen. 2004. MtDNA sequencing from zooplankton after long-term preservation in buffered formalin. Mol. Phylog. Evol. 30:879-882

Caudill, C.C. and A. Bucklin. 2004. Molecular phylogeography and evolutionary history of the estuarine copepod, Acartia tonsa, on the Northwest Atlantic coast. Hydrobiologia 511: 91-102



Bucklin, A., B.W. Frost, J. Bradford Grieve, L.D. Allen, and N.J. Copley. 2003. Molecular systematic assessment of thirty-four calanoid copepod species of the Calanidae and Clausocalanidae using DNA sequences of mtCOI and nuclear 18S rRNA. Mar. Biol. 142:333-343



Bucklin, A., P.H. Wiebe, S.B. Smolenack, and M.E. Clarke. 2002. Integrated biochemical, molecular genetic, and bioacoustical analysis of mesoscale variability of the euphausiid Nematoscelis difficilis in the California Current. Deep-Sea Res. I 49:437-462

McGillicuddy, D. J. Jr. and A. Bucklin. 2002. Intermingling of two Pseudocalanus species on Georges Bank. J. Mar. Res. 60:583-604

Wiebe, P.H., R. Beardsley, D. Mountain, and A. Bucklin. 2002. U.S. GLOBEC Atlantic / Georges Bank Program. Oceanography 15:13-29



Bucklin, A. et al., 2001. FleetLink: Collection and telemetry of ocean and weather data. Sea Technology, May, 2001

Bucklin, A., M. Guarnieri, D.J. McGillicuddy, and R.S. Hill. 2001. Spring evolution of Pseudocalanus spp. abundance on Georges Bank based on molecular discrimination of P. moultoni and P. newmani. Deep-Sea Res.  48:589-609

Hill, R.S., L.D. Allen, and A. Bucklin. 2001. Multiplexed species-specific PCR protocol to discriminate four N. Atlantic Calanus species, with a mtCOI gene tree for ten Calanus species. Mar. Biol. 139:279-287

Wiebe, P.H., R.C. Beardsley, A. Bucklin, and D.G. Mountain. 2001. Coupled biological and physical studies of plankton populations in the Georges Bank region and related North Atlantic GLOBEC sites. Deep-Sea Res. 48:1-2



Bucklin, A. 2000. Methods for Population Genetic Analysis of Zooplankton. Chapter 11 in: The Zooplankton Methodology Manual, International Council for the Exploration of the Sea. Academic Press, London. Pp. 533-570

Bucklin, A., S. Kaartvedt, M. Guarnieri, and U. Goswami. 2000. Population genetics of drifting (Calanus spp.) and resident (Acartia clausi) plankton in Norwegian fjords. J. Plank. Res. 22:1237-1251

Bucklin, A., P.H. Wiebe, O.S. Astthorsson, A. Gislason, L.D. Allen, and S.B. Smolenack. 2000. Population genetic variation of Calanus finmarchicus in Icelandic waters: preliminary evidence of genetic differences between Atlantic and Polar populations. ICES J. Mar. Res. 57:1592-1604