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John D. Fitzsimons

John D. Fitzsimons

D-Index & Metrics

Ecology and Evolution

D-Index
37
Citations
4408
World Ranking
6952
National Ranking
437

John D. Fitzsimons publication distribution in Ecology and Evolution in 2026

The chart shows the distribution of publications by all Research.com ranked scientists in the field of Ecology and Evolution in 2026. The highlighted bar marks where John D. Fitzsimons sits on this spectrum.

37–41 publications: 2 scientists 42–46 publications: 9 scientists 47–51 publications: 10 scientists 52–56 publications: 31 scientists 57–61 publications: 56 scientists 62–66 publications: 91 scientists 67–71 publications: 92 scientists 72–76 publications: 127 scientists 77–81 publications: 173 scientists 82–86 publications: 236 scientists 87–91 publications: 227 scientists 92–96 publications: 240 scientists 97–101 publications: 333 scientists 102–106 publications: 280 scientists 107–111 publications: 300 scientists 112–116 publications: 285 scientists 117–121 publications: 305 scientists 122–126 publications: 287 scientists 127–131 publications: 278 scientists 132–136 publications: 289 scientists 137–141 publications: 273 scientists 142–146 publications: 262 scientists 147–151 publications: 246 scientists 152–156 publications: 235 scientists 157–161 publications: 205 scientists 162–166 publications: 199 scientists 167–171 publications: 174 scientists 172–176 publications: 164 scientists 177–181 publications: 173 scientists 182–186 publications: 189 scientists 187–191 publications: 170 scientists 192–196 publications: 139 scientists 197–201 publications: 128 scientists 202–206 publications: 117 scientists 207–211 publications: 115 scientists 212–216 publications: 107 scientists 217–221 publications: 124 scientists 222–226 publications: 81 scientists 227–231 publications: 82 scientists 232–236 publications: 85 scientists 237–241 publications: 75 scientists 242–246 publications: 66 scientists 247–251 publications: 81 scientists 252–256 publications: 69 scientists 257–261 publications: 70 scientists 262–266 publications: 55 scientists 267–271 publications: 64 scientists 272–276 publications: 49 scientists 277–281 publications: 48 scientists 282–286 publications: 44 scientists 287–291 publications: 45 scientists 292–296 publications: 36 scientists 297–301 publications: 39 scientists 302–306 publications: 38 scientists 307–311 publications: 30 scientists 312–316 publications: 34 scientists 317–321 publications: 25 scientists 322–326 publications: 22 scientists 327–331 publications: 28 scientists 332–336 publications: 30 scientists 337–341 publications: 22 scientists 342–346 publications: 30 scientists 347–351 publications: 26 scientists 352–356 publications: 22 scientists 357–361 publications: 29 scientists 362–366 publications: 21 scientists 367–371 publications: 12 scientists 372–376 publications: 18 scientists 377–381 publications: 17 scientists 382–386 publications: 13 scientists 387–391 publications: 21 scientists 392–396 publications: 13 scientists 397–401 publications: 10 scientists 402–406 publications: 15 scientists 407–411 publications: 8 scientists 412–416 publications: 9 scientists 417–421 publications: 8 scientists 422–426 publications: 4 scientists 427–431 publications: 10 scientists 432–436 publications: 10 scientists 437–441 publications: 5 scientists 442–446 publications: 4 scientists 447–451 publications: 10 scientists 452–456 publications: 2 scientists 457–461 publications: 4 scientists 462–466 publications: 7 scientists 467–471 publications: 7 scientists 472–476 publications: 6 scientists 477–481 publications: 6 scientists 482–486 publications: 3 scientists 487–491 publications: 3 scientists 492–496 publications: 4 scientists 497–501 publications: 4 scientists 502–506 publications: 8 scientists 507–511 publications: 5 scientists 512–516 publications: 4 scientists 517–521 publications: 5 scientists 522–526 publications: 4 scientists 527–530 publications: 5 scientists 531+ publications: 100 scientists
37 publications 531+

This scientist: 93 publications — 14th percentile

14% of scientists in this discipline score the same or lower.

The last bar groups every scientist with 531 publications or more.

John D. Fitzsimons D-index placement in Ecology and Evolution in 2026

The chart shows the D-index (discipline H-index) distribution of Ecology and Evolution scientists ranked by Research.com in 2026. The highlighted bar marks where John D. Fitzsimons sits on this spectrum.

30 D-Index: 95 scientists 31 D-Index: 123 scientists 32 D-Index: 191 scientists 33 D-Index: 245 scientists 34 D-Index: 252 scientists 35 D-Index: 244 scientists 36 D-Index: 249 scientists 37 D-Index: 244 scientists 38 D-Index: 254 scientists 39 D-Index: 254 scientists 40 D-Index: 280 scientists 41 D-Index: 274 scientists 42 D-Index: 266 scientists 43 D-Index: 233 scientists 44 D-Index: 248 scientists 45 D-Index: 208 scientists 46 D-Index: 201 scientists 47 D-Index: 213 scientists 48 D-Index: 207 scientists 49 D-Index: 172 scientists 50 D-Index: 209 scientists 51 D-Index: 199 scientists 52 D-Index: 153 scientists 53 D-Index: 169 scientists 54 D-Index: 163 scientists 55 D-Index: 148 scientists 56 D-Index: 120 scientists 57 D-Index: 146 scientists 58 D-Index: 137 scientists 59 D-Index: 140 scientists 60 D-Index: 104 scientists 61 D-Index: 119 scientists 62 D-Index: 118 scientists 63 D-Index: 99 scientists 64 D-Index: 77 scientists 65 D-Index: 100 scientists 66 D-Index: 86 scientists 67 D-Index: 83 scientists 68 D-Index: 75 scientists 69 D-Index: 94 scientists 70 D-Index: 57 scientists 71 D-Index: 68 scientists 72 D-Index: 59 scientists 73 D-Index: 63 scientists 74 D-Index: 66 scientists 75 D-Index: 60 scientists 76 D-Index: 42 scientists 77 D-Index: 49 scientists 78 D-Index: 39 scientists 79 D-Index: 37 scientists 80 D-Index: 43 scientists 81 D-Index: 41 scientists 82 D-Index: 45 scientists 83 D-Index: 34 scientists 84 D-Index: 40 scientists 85 D-Index: 35 scientists 86 D-Index: 55 scientists 87 D-Index: 24 scientists 88 D-Index: 24 scientists 89 D-Index: 30 scientists 90 D-Index: 23 scientists 91 D-Index: 25 scientists 92 D-Index: 27 scientists 93 D-Index: 27 scientists 94 D-Index: 13 scientists 95 D-Index: 23 scientists 96 D-Index: 12 scientists 97 D-Index: 14 scientists 98 D-Index: 19 scientists 99 D-Index: 16 scientists 100 D-Index: 14 scientists 101 D-Index: 5 scientists 102 D-Index: 21 scientists 103 D-Index: 16 scientists 104 D-Index: 10 scientists 105 D-Index: 7 scientists 106 D-Index: 7 scientists 107 D-Index: 7 scientists 108 D-Index: 6 scientists 109 D-Index: 9 scientists 110 D-Index: 11 scientists 111 D-Index: 12 scientists 112 D-Index: 9 scientists 113 D-Index: 7 scientists 114 D-Index: 3 scientists 115 D-Index: 8 scientists 116 D-Index: 5 scientists 117 D-Index: 11 scientists 118 D-Index: 4 scientists 119 D-Index: 2 scientists 120 D-Index: 5 scientists 121+ D-Index: 100 scientists
30 D-Index 121+

This scientist: 37 D-Index — 20th percentile

20% of scientists in this discipline score the same or lower.

The last bar groups every scientist with 121 D-Index or more.

Overview

John D. Fitzsimons is affiliated with Fisheries and Oceans Canada in Canada. Their research primarily focuses on fish ecology and management, aquaculture nutrition and growth, with additional work in isotope analysis in ecology and physiological and biochemical adaptations. The main fields of study include environmental science as well as agricultural and biological sciences, with subfields in nature and landscape conservation, ecology, and aquatic science.

Recent publications by John D. Fitzsimons include detailed investigations into fish biology and conservation. Notable papers are:

  • Reduced thiamine utilization by Seneca Lake lake trout embryos and potential implications to restoration of lake trout in the Great Lakes, 2021, Environmental Biology of Fishes
  • Ontogenetic Dietary Changes and Thiamine Status of Lake Ontario Chinook Salmon, 2005-2006, 2021, North American Journal of Fisheries Management
  • Thiamine status of lake trout in lake Ontario and its relation to diet after the colonization of round goby, 2005-2006, 2021, Journal of Great Lakes Research

Frequent co-authors in Fitzsimons's publications include:

  • Dale C. Honeyfield
  • Scott A. Rush
  • Scott Brown
  • A. H. El-Shaarawi
  • Brian F. Lantry

Publication venues frequently featuring Fitzsimons's work are:

  • Environmental Biology of Fishes
  • North American Journal of Fisheries Management
  • Journal of Great Lakes Research

The scientist's research topics place strong emphasis on the ecological and nutritional factors affecting fish species. These topics are:

  • Fish Ecology and Management Studies
  • Aquaculture Nutrition and Growth
  • Isotope Analysis in Ecology
  • Physiological and biochemical adaptations

Best Publications

  • Lake Ontario: food web dynamics in a changing ecosystem (1970-2000)

    E L Mills;J M Casselman;R Dermott;J D Fitzsimons

  • A review of Early Mortality Syndrome (EMS) in Great Lakes salmonids. Relationship with thiamine deficiency

    J.D. Fitzsimons;S.B. Brown;D.C. Honeyfield;J.G. Hnath

  • Naturally Occurring Thiamine Deficiency Causing Reproductive Failure in Finger Lakes Atlantic Salmon and Great Lakes Lake Trout

    Jeffrey P. Fisher;John D. Fitzsimons;Gerald F. Combs;Jan M. Spitsbergen

  • Development of Thiamine Deficiencies and Early Mortality Syndrome in Lake Trout by Feeding Experimental and Feral Fish Diets Containing Thiaminase

    Dale C. Honeyfield;Joy P. Hinterkopf;John D. Fitzsimons;Donald E. Tillitt

  • Thiamine and Thiaminase Status in Forage Fish of Salmonines from Lake Michigan

    Donald E. Tillitt;James L. Zajicek;Scott B. Brown;Lisa R. Brown

  • The Effect of B-Vitamins on a Swim-up Syndrome in Lake Ontario Lake Trout

    John D. Fitzsimons

  • Implications of Thiamine Deficiency in Great Lakes Salmonines

    Scott B. Brown;John D. Fitzsimons;Dale C. Honeyfield;Donald E. Tillitt

  • Lake Trout Spawning Habitat in the Great Lakes — a Review of Current Knowledge

    J. Ellen Marsden;John M. Casselman;Thomas A. Edsall;Robert F. Elliott

  • Assessment of Lake Trout Spawning Habitat and Egg Deposition and Survival in Lake Ontario

    John D. Fitzsimons

  • Thiamine Status in Adult Salmonines in the Great Lakes

    Scott B. Brown;Dale C. Honeyfield;John G. Hnath;Martha Wolgamood

  • Thiamine analysis in fish tissues.

    S. B. Brown;D. C. Honeyfield;L. Vandenbyllaardt;G. McDonald

  • The Influence of the Niagara River on Contaminant Burdens of Lake Ontario Biota

    D.M. Whittle;J.D. Fitzsimons

  • Experimental Induction of Liver Tumours in Rainbow Trout (Salmo gairdneri) by Contaminated Sediment from Hamilton Harbour, Ontario

    C. D. Metcalfe;V. W. Cairns;J. D. Fitzsimons

  • Influences of Spawning Habitat Characteristics and Interstitial Predators on Lake Trout Egg Deposition and Mortality

    Randall M. Claramunt;Jory L. Jonas;John D. Fitzsimons;J. Ellen Marsden

  • Estimates of egg deposition and effects of lake trout (Salvelinus namaycush) egg predators in three regions of the Great Lakes

    Jory L Jonas;Randall M Claramunt;John D Fitzsimons;J Ellen Marsden

  • Carcinogenic and genotoxic activity of extracts from contaminated sediments in western Lake Ontario.

    C.D. Metcalfe;G.C. Balch;V.W. Cairns;J.D. Fitzsimons

  • Occurrence of a Swim-up Syndrome in Lake Ontario Lake Trout in Relation to Contaminants and Cultural Practices

    John D. Fitzsimons;Susan Huestis;Bill Williston

  • Egg Thiamine Status of Lake Ontario Salmonines 1995–2004 with Emphasis on Lake Trout

    John D. Fitzsimons;Bill Williston;Georgina Williston;Lisa Brown

  • Reduced egg thiamine levels in inland and Great Lakes lake trout and their relationship with diet.

    J. D. Fitzsimons;S. B. Brown;G. McDonald;D.C. Honeyfield

  • Sculpins and Crayfish in Lake Trout Spawning Areas in Lake Ontario: Estimates of Abundance and Egg Predation on Lake Trout Eggs

    John D. Fitzsimons;David L. Perkins;Charles C. Krueger

  • Thiamine Content and Thiaminase Activity of Ten Freshwater Stocks and One Marine Stock of Alewives

    John D. Fitzsimons;Bill Williston;James L. Zajicek;Donald E. Tillitt

  • Early life stage mortality syndrome in fishes of the Great Lakes and Baltic Sea

    D. G. McDonald;John D. Fitzsimons;Dale C. Honeyfield

Frequent Co-Authors

Donald E. Tillitt
Donald E. Tillitt United States Geological Survey
J. Ellen Marsden
J. Ellen Marsden University of Vermont
Timothy B. Johnson
Timothy B. Johnson Ministry of Natural Resources and Forestry
Michael T. Arts
Michael T. Arts Toronto Metropolitan University
Charles C. Krueger
Charles C. Krueger Michigan State University
John M. Casselman
John M. Casselman Queen's University
Chris D. Metcalfe
Chris D. Metcalfe Trent University
Lars G. Rudstam
Lars G. Rudstam Cornell University
Chris C. Wilson
Chris C. Wilson Ministry of Natural Resources and Forestry
Clifford E. Kraft
Clifford E. Kraft Cornell University

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