Mendez-Macfas et al.: Trophic ecology and ontogenetic shift in the diet of Mustelus iunulatus in the southeastern Pacific Ocean 
249 
Table 1 
Diet composition for sickfefin smoothhounds ( Mustelus Iunulatus) in the southeastern Pacific Ocean, based on analysis of stomach 
contents of specimens collected from landings of an artisanal fishery at the port of Manta, Ecuador, between November 2003 and 
October 2004. Values provided for prey found in stomachs include percent abundance (percent number of samples [%N]), percent 
prey-specific abundance (percent number of samples for specific prey [%PN]), percent weight (%W), percent prey-specific weight 
(percent weight of specific prey [%PW]), percent frequency of occurrence (%FO), and prey-specific index of relative importance 
(PSIRI). Trophic position (TP) values are taken from Hobson and Welch (1992), Cortes (1999), Sea Around Us (2015), and FishBase 
(2016). A dash indicates that data were not available because a value was not estimated. 
Prey 
%N 
%PN 
%W 
%PW 
%FO 
PSIRI (%) 
TP 
ARTHROPODA 
88.17 
90.59 
89.03 
91.48 
97.32 
88.60 
2.52 
Guyanacaris caespitosa 
0.11 
33.33 
0.18 
53.54 
0.30 
0.15 
3.43 
Acanthocarpus delsolari 
4.29 
64.17 
4.20 
62.74 
6.70 
4.25 
2.52 
Calappula saussurei 
5.13 
36.51 
4.43 
31.54 
14.00 
4.78 
3.60 
Cycloes bardii 
0.17 
50.00 
0.23 
67.90 
0.30 
0.19 
2.52 
Ethusa spp. 
2.40 
34.22 
2.29 
32.63 
7.00 
2.34 
2.60 
Euphylax robustus 
1.99 
37.28 
2.77 
51.84 
5.30 
2.36 
4.00 
Diogenidae 
0.07 
20.00 
0.03 
8.88 
0.30 
0.05 
2.50 
Penaeidae 
0.02 
6.67 
<0.01 
0.48 
0.20 
0.01 
3.31 
Goneplax spp. 
0.44 
26.38 
0.51 
30.79 
1.70 
0.49 
2.82 
Hemisquilla spp. 
0.08 
25.00 
0.01 
1.53 
0.30 
0.04 
3.50 
Hepatus kossmanni 
0.08 
25.00 
0.10 
30.35 
0.30 
0.09 
2.60 
Iliacantha spp. 
46.00 
41.05 
46.00 
40.33 
15.40 
6.27 
2.60 
Mesorhoea belli 
0.83 
31.15 
0.47 
17.38 
2.70 
0.66 
2.52 
Munida hispida 
0.11 
33.33 
0.07 
22.17 
0.30 
0.09 
3.10 
Munida refulgens 
1.01 
38.02 
0.97 
36.29 
2.70 
0.99 
3.10 
Panopeus spp. 
1.09 
29.55 
0.98 
26.62 
3.70 
1.04 
3.38 
Parasquilla similis 
0.04 
12.50 
0.02 
6.63 
0.30 
0.03 
2.52 
Parthenope spp. 
0.84 
25.24 
0.68 
20.46 
3.30 
0.75 
2.52 
Pilumnus fernandezi 
0.87 
43.52 
0.85 
42.34 
2.00 
0.86 
2.52 
Plesionika mexicana 
0.17 
50.00 
0.06 
17.77 
0.30 
0.10 
2.70 
Platymera gaudichaudii 
1.52 
64.76 
1.53 
65.37 
2.30 
1.50 
2.52 
Achelous iridescens 
30.16 
60.12 
29.12 
58.05 
50.20 
29.66 
3.40 
Portunus asper 
0.84 
83.33 
0.91 
90.99 
1.00 
0.87 
3.40 
Ranilia spp. 
1.09 
36.28 
1.05 
34.90 
3.00 
1.07 
2.52 
Sicyonia disdorsalis 
0.06 
16.67 
0.04 
11.24 
0.30 
0.05 
2.40 
Sicyonia picta 
0.21 
31.25 
0.16 
23.25 
0.70 
0.19 
2.40 
Solenocera agassizi 
0.36 
26.90 
0.50 
37.69 
1.30 
0.43 
2.20 
Solenocera spp. 
0.17 
25.89 
0.14 
21.38 
0.70 
0.17 
2.20 
Squilla biformis 
0.81 
48.33 
0.80 
48.02 
1.70 
0.82 
3.50 
Squilla hancocki 
0.37 
27.92 
0.22 
16.16 
1.30 
0.29 
3.50 
Squilla panamensis 
4.22 
40.08 
4.36 
43.46 
10.00 
4.29 
3.50 
Squilla spp. 
2.82 
38.26 
2.31 
31.41 
7.40 
2.58 
3.50 
Rimapenaeus pacificus 
0.06 
16.67 
0.01 
3.29 
0.30 
0.03 
2.52 
Trizocarcinus dentatus 
0.22 
22.22 
0.16 
5.74 
1.00 
0.19 
2.52 
Crustacean remains 
19.18 
48.19 
22.66 
56.93 
39.80 
20.92 
2.52 
OSTEICHTHYES 
5.87 
39.89 
5.39 
36.59 
14.72 
5.63 
3.24 
Anchoa spp. 
0.26 
77.78 
0.14 
43.02 
0.33 
0.20 
3.25 
Auxis spp. 
0.94 
40.36 
1.07 
45.54 
2.34 
1.01 
4.24 
Bollmannia chlamydes 
0.17 
50.00 
0.28 
82.23 
0.33 
0.22 
3.50 
Citharichthys gilberti 
0.17 
50.00 
0.08 
25.33 
0.33 
0.13 
4.10 
Citharichthys platophrys 
0.08 
25.00 
0.03 
10.29 
0.33 
0.06 
3.50 
Paralichthyidae 
0.03 
9.09 
0.02 
5.21 
0.33 
0.02 
4.06 
Pleuronectiformes 
0.12 
37.50 
0.17 
52.07 
0.33 
0.15 
3.57 
Unidentified fish 
0.56 
55.56 
0.51 
50.40 
1.00 
0.53 
3.24 
Symphurus spp. 
0.15 
22.92 
0.05 
6.99 
0.67 
0.10 
3.30 
Fish remains 
3.38 
38.89 
3.04 
34.93 
8.70 
3.21 
3.24 
MOLLUSCA 
5.76 
44.13 
5.34 
40.98 
13.04 
5.55 
3.20 
Gastropoda 
0.29 
28.89 
0.07 
6.49 
1.00 
0.18 
2.10 
Lolliguncula (Loliolopsis) diomedeae 
4.01 
45.36 
3.69 
40.83 
9.03 
3.89 
3.90 
Squid remains 
1.37 
45.49 
1.59 
52.89 
3.01 
1.48 
3.20 
Unidentified organic matter 
0.20 
20.37 
0.23 
23.28 
1.00 
0.22 
- 
