Fróðskaparrit - 01.01.2002, Page 136

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ECOLOGY OF ENDOPARASITES OF THE ATLANTIC PUFFIN
Table 1. Endoparasites in puffins (Number of examined birds; Number ofinfested birds; percent of birds
infested (prevalence); Mean number of parasites in the infested birds (relative mean); The numerícal range of
parasites in the infested birds.
Talva 1. Innvortis snýkar í lunda (Tal av kannaðum fuglum; Tal av fongdum fuglum; Prosent av fongdum
fuglum (Útbreiðsla); Miðal nøgd av snýkum í fongdum fuglum; Minsta- og mesta nøgd av snýkum í fongdum
fuglum).
No. oí’ birds cxamined No. of birds infested Prevalence (%) Relative mean nunibcr of parasites (±lstd. error) Numcrical range parasites in infested birds
Trematodes 173 62 35.8 5.0 (±1.0) 1-33
Cestodes 173 55 31.8 2.0 (±0.3) 1-14
Nematodes 173 37 21.4 1.4 (±0.1) 1- 4
Pcntastomes 173 4 2.3 11.8 (±8.6) 1-37
the linings of various organs. (See Table 2,
for position and number of parasites).
Host specific aspects
Host fitness
There was no difference in fitness between
infested- and not infested birds (t-test, t173=
0.123, p=0.90). The weight of the abdomi-
nal fat reserves was divided into two cate-
gories: <0.4 g, and >0.4 g. Comparing these
two groups, there was no difference regard-
ing the mean intensity of infestation with
trematodes (M-W, U=3079; p=0.80) or ces-
todes (t-test, tn3= -0.115, p=0.91), but
birds with the higher abdominal fat re-
serves had higher intensities of nematode
infestation (M-W, U=2642; p=0.02). The
mean weight of the abdominal fat reserves
in the four birds, infested with pentastomes
was 0.4 g, the same as in birds not infested
by parasites (the weight was 0.3 g in the
puffin that harboured 37 specimens).
Host sex
There was no sexual bias with respect to
prevalence of infestation: trematodes (Fis-
cher’s exact test, p=0.08), cestodes (Fisch-
er’s exact test, p=0.87), and nematodes
(Fischer’s exact test, p=0.27). Furthermore,
there was no difference in mean intensity of
infestation: trematodes (M-W, U=3361;
p=0.21), cestodes (M-W, U=3554; p=0.57),
and nematodes (M-W, U=3423; p=0.22).
Three of the four birds infested with pen-
tastomes were female. Considering the rel-
ative intensity of helminth infestation in the
birds, males were significantly more heavi-
ly infested with trematodes than females
(M-W, U=337; p=0.04), and a non-signifi-
cant difference was showafor cestodes (M-
W, U=379; p=0.07), but not for nematodes
(t-test, t35= -0.91, p=0.37).
Host age
The mean intensity of infestation did not
differ between the two age classes for
trematodes (M-W, U=3341, p=0.52), ces-
todes (M-W, U=3129, p=0.15) or nema-
todes (t-test, t,7()=0.12, p=0.91). Regarding
the relative intensity of infestation, there