Electronic Appendix S1: Number of seeds of each species fed to Colossoma individuals. The size of captive fish was not determined in 2004 and 2005, but those individuals were as large as the 2006 adults. Adult fish were used in all three years, but juveniles were only included in 2006.

Species (Family) / Year / Number of seeds fed per fish per trial / Number of fish / Number of trials / SL (mean + SE)
Cecropia latiloba (Urticaceae) / 2004, 2005, 2006 / 2004: >100
2005: 200
2006: 60 / 2004: 5
2005: 5
2006: 4 adults; 5 juveniles / 2004: 2
2005: 3
2006: 3 / Adults: 39.67 + 0.33
Juveniles:
24 + 0.35
Duroia duckei (Rubiaceae) / 2004, 2005, 2006 / 2004: >100
2005: 100
2006: 60 (2 trials) and 70 (1 trial) / 2004: 5
2005: 5
2006: 4 adults; 5 juveniles / 2004: 2
2005: 3
2006: 3 / Adults: 39.67 + 0.33
Juveniles:
24 + 0.35
Cayaponia tubulosa (Cucurbitaceae) / 2006 / 5 to adults; 3 to juveniles / 5 adults; 4 juveniles / 1 / Adults: 49.8 + 5.09
Juveniles:
23.9 + 0.43
Cayaponia cruegeri (Cucurbitaceae) / 2005 / 15 / 5 / 2
Annona muricata (Annonaceae) / 2006 / 7 to adults; 4 to juveniles / 5 adults; 5 juveniles / 1 / Adults: 48 + 4.93
Juveniles:
23.1 + 0.48
Crateva tapia (Capparaceae) / 2006 / 10 (1 trial) and 12 (1 trial) / 3 adults; 4 juveniles for 1 trial, and 5 for the second trial / 2 / Adults: 39.67 + 0.33
Juveniles:
23.4 + 0.38
Bactris bidentula (Arecaceae) / 2006 / 7 to adults; 4 to juveniles / 5 adults; 5 juveniles / 1 / Adults: 39.67 + 0.33
Juveniles:
23.1 + 0.48

Electronic Appendix S2: Intact seeds present in the digestive tracts of Colossoma (n=144) and

Piaractus (n=51) individuals at Pacaya-Samiria National reserve. The occurrence columns report

the number of individual fish with intact seeds of each plant species in their digestive tracts. Species that were also present in the botanical transects are noted with an asterix.

Colossoma macropomum / Piaractus brachypomus
Species of seed / Number of seeds / Occurrence / Number of seeds / Occurrence / Wet seed mass (g)C
Cecropia spp.a (Urticaceae)* / 698185B / 111 / 406895 / 39 / 0.0054 + 0.001
Duroia duckei (Rubiaceae)* / 1353 / 14 / 91 / 4 / 0.031 + 0.024
Bactris maraja (Arecaceae)* / 8 / 3 / 128 / 6 / 2.19 + 0.99
Bactris bidentula (Arecaceae)* / 99 / 8 / 127 / 12 / 1.26 + 0.26
Crateva tapia (Capparaceae)* / 88 / 12 / 19 / 4 / 0.54 + 0.29
Cayaponia cruegeri (Cucurbitaceae) / 70 / 2 / 0 / 0 / 0.076 + 0.013
Carica microcarpa (Caricaraceae) / 0 / 0 / 73 / 1 / 0.048 + 0.027
Annona muricata (Annonaceae)* / 10 / 3 / 53 / 2 / 0.61 + 0.26
Genipa spruceana (Rubiaceae) / 0 / 0 / 46 / 2 / 0.34 + 0.20
Ternstroemia penduliflora (Theaceae) / 41 / 1 / 0 / 0 / 0.44
Unidentified 1 / 0 / 0 / 37 / 1 / 0.11
Maclura tinctoria (Moraceae)* / 34 / 2 / 0 / 0 / Unmeasured
Cayaponia tubulosa (Cucurbitaceae)* / 26 / 5 / 24 / 5 / 2.54 + 0.68
Maquira coriacea (Moraceae) / 24 / 1 / 0 / 0 / Unmeasured
Bactris sp. (Arecaceae) / 0 / 0 / 23 / 1 / 1.22
Endlicheria sp.
(Lauraceae) / 0 / 0 / 10 / 1 / 5.25
Unidentified 2 / 9 / 1 / 0 / 0 / 0.6
Neea floribunda
(Nyctaginaceae) / 0 / 0 / 8 / 1 / 0.31
Chrysophyllum argenteum (Sapotaceae) / 6 / 1 / 5 / 1 / 0.83
Ceiba samauma
(Bombacaceae) / 0 / 0 / 5 / 3 / 0.42 + 0.12
Unidentified 4 / 0 / 0 / 4 / 1 / 0.23
Leonia glycycarpa (Violaceae)* / 3 / 1 / 0 / 0 / 0.5
Pouteria sp.
(Sapotaceae) / 0 / 0 / 3 / 2 / 4.43 + 0.11
Unidentified 5 / 0 / 0 / 2 / 1 / 0.75
Cordia ulei (Boraginaceae) / 0 / 0 / 2 / 1 / 0.75
Pouteria cladantha (Sapotaceae)* / 1 / 1 / 0 / 0 / 1.5
Ocotea sp.
(Lauraceae)* / 1 / 1 / 0 / 0 / Unmeasured
Discophora guianensis
(Icacinaceae) / 1 / 1 / 0 / 0 / Unmeasured
Simaba polyphylla
(Simaroubaceae) / 1 / 1 / 0 / 0 / 0.85
Unidentified 6 / 1 / 1 / 0 / 0 / 0.3
Unidentified 7 / 1 / 1 / 0 / 0 / 0.2
Unidentified 8 / 1 / 1 / 0 / 0 / 1.4
Astrocaryum sp. (Arecaceae) / 0 / 0 / 1 / 1 / 2.1
Dulacia candida (Olacaceae) / 0 / 0 / 1 / 1 / 0.4
Unidentified 9 / 0 / 0 / 1 / 1 / 9.9

aSince Cecropia seeds are smalldifficult to identify to species, we pooled at least two species of including C.latiloba and membranacea. We included two Cecropia species in the estimate of species diversity of intact seeds in the diets of Piaractus and Colossoma.

B We weighed all Cecropia seeds, and estimated seed number based on the following regression model (F1,13=626.4, p<0.0001, R2=0.98): Seed number = 78.1 + 162.01 * weight (g).

C Seeds from the digestive tract of each individual were pooled. Averages and standard deviations are based on seed numbers and the pooled weights. When a species is present only in the digestive tract of on individual, there is no standard deviation. We did not record seed mass in 2004.

Electronic appendix S3: Cumulative number of plant species whose intact seeds were present in the digestive tracts of Colossoma and Piaractus, 2004-2006.

Electronic appendix S4: Species composition, abundance, and fruit production from botanical transects. The habitat affinity of plant species (floodplain forest or savannah) is included as well as whether intact seeds were present in the digestive systems of Colossoma macropomum, Piaractus brachypomus, or both species. Species are organized in descending order of abundance.

habitat / species / family / number of fruiting plants / total number of fruits / Intact seeds in digestive systems? / growth form
both / Cecropia latiloba / Urticaceae / 39 / 3404 / both / pioneer tree
both / Crateva tapia / Capparidaceae / 32 / 483 / both / tree
both / Duroia duckei / Rubiaceae / 18 / 718 / both / tree
floodplain forest / Eugenia discreta / Myrtaceae / 15 / 1738 / small tree
both / Pseudobombax munguba / Bombacaceae / 10 / 76 / tree
both / Leonia glycycarpa / Violaceae / 9 / 98 / Colossoma / tree
both / Maripa peruviana / Convolvulaceae / 9 / 3323 / liana
floodplain forest / Neea virens / Nyctaginaceae / 9 / 2707 / tree
both / Annona muricata / Annonaceae / 8 / 37 / both / tree
floodplain forest / Guarea macrophylla / Meliaceae / 7 / 557 / tree
both / Tococa capitata / Melastomataceae / 7 / 257 / small tree
floodplain forest / Bactris bidentula / Arecaceae / 6 / 213 / both / tree
floodplain forest / Rudgea sessiliflora / Rubiaceae / 6 / 526 / small tree
floodplain forest / Margaritaria nobilis / Euphorbiaceae / 5 / 130 / tree
floodplain savannah / Psittacanthus calcaratus / Loranthaceae / 5 / 827 / parasitic liana
both / Alibertia stenantha / Rubiaceae / 4 / 41 / small tree
floodplain forest / Coccoloba densifrons / Polygonaceae / 4 / 265 / tree
floodplain forest / Duguetia spixiana / Annonaceae / 4 / 23 / tree
floodplain forest / Inga punctata / Fabaceae / 4 / 33 / tree
both / Iryanthera tessmannii / Myristicaceae / 4 / 1090 / tree
floodplain forest / Trymatococcus amazonicus / Moraceae / 4 / 2550 / tree
floodplain forest / Doliocarpus dentatus / Dilleniaceae / 3 / 111 / liana
flooded savannah / Eugenia egensis / Myrtaceae / 3 / 1945 / small tree
floodplain forest / Ficus krukovii / Moraceae / 3 / 318 / tree
both / Rourea camptoneura / Connaraceae / 3 / 5111 / liana
floodplain forest / Swartzia auriculata / Fabaceae / 3 / 67 / small tree
floodplain forest / Allophylus loretensis / Sapindaceae / 2 / 662 / liana
floodplain forest / Bactris maraja / Arecaceae / 2 / 100 / both / tree
both / Cayaponia tubulosa / Cucurbitaceae / 2 / 13 / both / liana
both / Cecropia membranacea / Urticaceae / 2 / 140 / both / Pioneer tree
floodplain forest / Dioclea ucayalina / Fabaceae / 2 / 5 / liana
floodplain forest / Eugenia florida / Myrtaceae / 2 / 75 / small tree
both / Garcinia madruno / Clusiaceae / 2 / 39 / tree
both / Gnetum nodiflorum / Gnetaceae / 2 / 280 / liana
floodplain savannah / Maclura tinctoria / Moraceae / 2 / 392 / Colossoma / tree
floodplain forest / Ouratea iquitosensis / Ochnaceae / 2 / 7 / small tree
both / Paullinia clavigera / Sapindaceae / 2 / 85 / liana
floodplain forest / Paullinia grandifolia / Sapindaceae / 2 / 830 / liana
both / Phthirusa retroflexa / Loranthaceae / 2 / 1700 / liana
floodplain forest / Pinzona coriacea / Dilleniaceae / 2 / 15004 / liana
floodplain forest / Pouteria glomerata / Sapotaceae / 2 / 30 / tree
floodplain forest / Pseudoxandra polyphleba / Annonaceae / 2 / 40 / tree
floodplain forest / Strychnos guianensis / Loganiaceae / 2 / 164 / liana
floodplain forest / Tetracera parviflora / Dilleniaceae / 2 / 30000 / liana
floodplain forest / Allophylus floribundus / Sapindaceae / 1 / 10000 / liana
floodplain forest / Unknown / Unknown / 1 / 1
floodplain savannah / Pouteria cladantha / Sapotaceae / 1 / 20 / Colossoma / tree
floodplain savannah / Calyptranthes creba / Myrtaceae / 1 / 1 / small tree
floodplain forest / Clarisia racemosa / Moraceae / 1 / 10000 / tree
floodplain forest / Clitoria falcata / Fabaceae / 1 / 13 / liana
floodplain savannah / Couepia subcordata / Chrysobalanaceae / 1 / 26 / tree
flooded savannah / Couepia williamsii / Chrysobalanaceae / 1 / 52 / tree
floodplain forest / Curarea toxicofera / Menispermaceae / 1 / 53 / liana
floodplain forest / Cynometra bauhiniifolia / Fabaceae / 1 / 69 / tree
floodplain forest / Diospyros poeppigiana / Ebenaceae / 1 / 39 / tree
floodplain forest / Faramea amplifolia / Rubiaceae / 1 / 90 / small tree
floodplain forest / Ficus americana / Moraceae / 1 / 10000 / tree
floodplain forest / Ficus gomelleira / Moraceae / 1 / 4 / tree
floodplain forest / Ficus maxima / Moraceae / 1 / 8000 / tree
floodplain forest / Ficus trigona / Moraceae / 1 / 200 / tree
floodplain forest / Guatteria inundata / Annonaceae / 1 / 105 / liana
floodplain forest / Guettarda aromatica / Rubiaceae / 1 / 1 / liana
floodplain forest / Licania heteromorpha / Chrysobalanaceae / 1 / 66 / tree
floodplain forest / Ocotea sp. / Lauraceae / 1 / 30000 / Colossoma / tree
floodplain savannah / Phthirusa pyrifolia / Loranthaceae / 1 / 420 / liana
floodplain forest / Picramnia sellowii / Simaroubaceae / 1 / 183 / small tree
floodplain forest / Psidium acutangulum / Myrtaceae / 1 / 300 / small tree
floodplain forest / Psychotria barbiflora / Rubiaceae / 1 / 78 / small tree
floodplain savannah / Rheedia gardneriana / Clusiaceae / 1 / 2000 / tree
floodplain forest / Salacia impressifolia / Hippocrateaceae / 1 / 71 / liana
floodplain forest / Salacia macrantha / Hippocrateaceae / 1 / 1 / liana
floodplain forest / Simira rubescens / Rubiaceae / 1 / 700 / small tree
floodplain forest / Sloanea guianensis / Elaeocarpaceae / 1 / 50 / tree
floodplain savannah / Solanum acuminatum / Solanaceae / 1 / 5 / small tree
floodplain forest / Solanum stramoniifolium / Solanaceae / 1 / 45 / small tree
floodplain savannah / Symmeria paniculata / Polygonaceae / 1 / 25 / small tree
floodplain forest / Tetracera volubilitis / Ebenaceae / 1 / 25 / liana
floodplain forest / Xylosma benthamii / Flacourtiaceae / 1 / 4000 / small tree
floodplain forest / Unknown / Unknown / 1 / 1

Electronic appendix S5: Intact seeds present in the digestive tracts of Piaractus brachypomus (n=15), Caura river, Venezuela, June-July 2002. Germination trials were not conducted with these seeds.

Species / Number of seeds / Occurrence
Crescentia amazonica (Bignoniaceae) / 1460 / 4
Cecropia spp. (Urticaeae) / 1224 / 1
Unidentified 1 (Sapotaceae) / 208 / 10
Brysonima sp. (Malpighiaceae) / 50 / 6
Unidentified 2 (Myrtaceae) / 26 / 4
Unidentified 3 (Sapotaceae) / 28 / 2
Unidentified 4 / 14 / 1
Ocotea sp. (Lauraceae) / 9 / 2
Astrocaryum jauari (Arecaceae) / 8 / 1
Unidentified 5 / 2 / 1
Trichilia sp. (Meliaceae) / 1 / 1
Unidentified 6 / 1 / 1
Unidentified 7 (Sapotaceae) / 1 / 1
Unidentified 8 / 1 / 1
Unidentified 9 / 1 / 1
Unidentified 10 / 1 / 1

Note: Fishes were captured in gill nets, and no bait was used.

Electronic Appendix S6: Intact seeds present in the diets of Byrcon bicolor (n=104; an additional 4 individuals had empty digestive tracts) June 2002, Ventuari River, Venezuela. A subset of these seeds was used in a pilot germination study. We dissected the digestive tracts of 69 individuals separately, and we pooled the digestive tracts of 39 individuals that were obtained from local fishers. Here, data on the total number of seeds are presented for all 104 individuals in this study. Data on the occurrence of a species of seed in the diet of B. bicolor is based only on fish for which we have individual-level data (60 of 69 fish had intact seeds in their digestive systems).

Species (Family) / Total number of seeds present in digestive tracts / Occurrence: number of individual fish (of 60) with each species of seed in the digestive system. / Germinated after 3 weeks?
Genipa americana (Rubiaceae) / 329 / 3 / Yes
Leopoldinia pulchra (Arecaceae) / 151, plus 46 in pooled sample / 44 (4 additional fish had fruit pulp of this species, but no seeds) / NoA
Clusia sp. (Clusiaceae) / 69, plus 68 in pooled sample / 11 / YesB
Unidentified 1 / 23 / 2 / Yes
Byrsonima sp. (Malpighiaceae) / 13 / 6
Unidentified 2 (Myrtaceae) / 12 / 3 / Yes
Quiina sp. (Quiinaceae) / 10 / 3 / Yes
Trichilia sp. (Meliaceae) / 7 in pooled sample / Yes
Unidentified 3 / 7 / 3
Unidentified 4 (Myrtaceae) / 6 / 4 / Yes
Unidentified 5 (Olacaceae) / 5 / 2 / Yes
Strychnos sp. (Loganiaceae) / 5 / 1 / Yes
Unidentified 6 / 5 / 2 / Yes
Mauritia flexuosa
(Arecaceae) / 1, plus 3 in pooled sample / 1 / No
Unidentified 7 (Sapotaceae) / 3 / 2 / Yes
Astrocaryum jauari (Arecaceae) / 3 / 3 / No
Unidentified 8 / 2, in pooled sample / Yes
Unidentified 9 / 2, in pooled sample / Yes
Unidentified 10 / 2, in pooled sample
Ocotea sp. (Lauaraceae) / 1 / 1 / Yes
Unidentified 11 (Rubiaceae) / 1 / 1 / Yes
Unidentified 12 (Myrtaceae) / 1 / 1 / Yes
Unidentified 13 (Myrtaceae) / 1 / 1 / Yes
Unidentified 14 / 1, in pooled sample / No
Unidentified 15 / 1 / 1 / Yes
Unidentified 16 / 1 / 1 / Yes
Unidentified 17 / 1 / 1 / No
Unidentified 18 / 1 / 1 / No
Unidentified 19 / 1 / 1 / No
Unidentified 20 / 1 / 1 / No
Unidentified 21 / 1 / 1 / No
Unidentified 22 / 1 / 1 / No

Note: Fish were captured on hooks bated with fruits of Ocotea sp. (Lauraceae); local fishermen report that this species is a major component of the diet of Brycon during July, and that seeds are found intact in the digestive system. Fruits of this species were not mature at the time of this study; Ocotea seeds found in the diet of Brycon came from the bait, except for one individual that had independently consumed Ocotea. This one individual is noted in the table. Fishermen harvested these fruits early for the purpose of capturing Brycon. We also attempted to capture fish with other bait, such as worms and small pieces of fish; these baits invariably did not succeed.

A A congener germinated only after 80-100 days (Kubitzki and Ziburski 1994).

B Seeds of Clusia sp. even germinated while submerged in water

Kubitzki, K., and A. Ziburski. 1994. Seed dispersal in flood plain forests of Amazonia. Biotropica 26:30-43.