Endocrine (sexual) disruption is not a prominent feature in the pike (Esox lucius), a top predator, living in english waters

Abstract

The high incidence of intersex roach (Rutilus rutilus) in some United Kingdom rivers that has been associated with exposure to sewage treatment works (STWs) effluent led us to hypothesize that top predator fish also may be affected by estrogenic chemicals, because they are likely to bioaccumulate lipophilic compounds through a predator-prey relationship. To investigate this possibility, pike (Esox lucius) were sampled both upstream and downstream of STWs and then examined for total estrogenic activity of their bile, as measured using a yeast-based estrogen assay to determine the degree of recent exposure of the pike to estrogens and vitellogenin induction, and for possible disruption of sexual development, as measured using histological analysis of the gonads. No evidence of severe disruption was found in the sampled fish, which came from 16 sampling sites that were representative of English rivers. However, 14% of pike were intersex, of which 15 of 16 showed patches of male germ cells among predominantly female gonadal tissue. The incidence of masculinization was independent of whether the pike had been sampled upstream or downstream of STWs. Although pike are gonochoristic, it is not known if this masculinization of presumptive female pike is normal or, instead, indicative of endocrine disruption. Vitellogenin concentrations were not elevated in male pike at sites either upstream or downstream of STWs. The results suggest that sexual disruption is not common in pike, a fish at the top of the food chain in the freshwaters of England.

Reproductive health of brown trout inhabiting Swiss rivers with declining fish catch

“…In contrast, Körner et al (2005) observed small nests fi lled with all stages of spermatogenesis occupying less than 1 % of the gonads. This fi nding, with a prevalence up to 27 %, is consistent with fi eld observations in Danish brown trout (Christiansen and Plesner, 2001), but also whitefi sh (Mikaelian et al, 2002) and pike (Vine et al, 2005), reporting a prevalence between 12 % and 26 %.…”

Ovarian alterations in wild northern pike Esox lucius females

“…Kipfer et al 2009 (and intersex) gonad tissues (Jobling et al 1998, van Aerle et al 2001, Noaksson et al 2001, Kavanagh et al 2004, Hanson 2009). Hermaphroditic histological changes in the ovaries have also been reported in northern pike (Dominguez et al 1989, Vine et al 2005. However, the results pre sented in the present pa per are the first data about extreme alterations of ovaries in northern pike, the top pre dator in freshwater food webs.…”

“…This is a possible aetiology of this phenomenon for northern pike as well, particularly given that 2 different environments were considered, and only one was subjected to industrial pollution (from the wastewater treatment plant). Also, Vine et al (2005) reported that the pollution originating from the treatment plant did not cause gonadal malformation in northern pike. However, to support the hypothesis that improper hatchery management can cause genetic changes resulting in gonadal alterations, a detailed evaluation is needed of the protocols in hatcheries where the restocked fry was produced as well as an evaluation of spawner origin and condition.…”

Evidence for estrogenic endocrine disruption in an offshore flatfish, the dab (Limanda limanda L.)

“…This is because, although cumulative and persistent weak estrogenic chemicals are almost certainly present in the freshwater environment, their effect would be very difficult to demonstrate in an environment dominated by shortlived but nevertheless far more potent compounds emanating from sewage treatment works and factories. However, one study ( Another study (Vine, Shears, van Aerle, Tyler, & Sumpter, 2005), that looked for effects in a top predator, the pike (Esox lucius) preying on estrogen-contaminated roach, found that, although the bile of male pike caught downstream had significantly more estrogenic activity than that of male pike caught upstream, there was no significant difference in VTG concentrations. Only two out of fifty-two male pike had detectable VTG in their plasma.…”