Naturalists Society

Bull Trout Spawn in the Fall

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Photo: oldmanwatershed.ca

Photo: thestar.com

Photo: letsgooutdoors.ca

Bull Trout usually reach sexual maturity between five and seven years of age.

Although Bull Trout are iteroparous, there is strong evidence that they display alternate-year spawning or resting periods between consecutive spawning events. This reproductive strategy, which is often condition and survival dependent, may enable them to accrue sufficient energy for reproduction in colder, less productive systems.

Like all char, Bull Trout spawn in the fall, from mid-

August to late October. Digging of the spawning site, or redd, and spawning is like that of other salmonids. Spawning usually occurs during the day but in some disturbed systems, spawning occurs at night. Bull Trout fecundity depends on female body size; the larger fluvial and ad-fluvial females produce more eggs (2000 - 5000+) than the smaller stream-resident females (< 1000). Fertilized eggs incubate in the gravel overwinter before fry typically hatch from March onwards. The incubation period is temperature dependent and can take from 35 days to more than 4 months.

Birds of Prey

Centre in Coaldale Daily Hours Open, 9:30 to 5:00 p.m.

For more information:

https://www.alberta.ca/ bull-trout.aspx https://letsgooutdoors.ca /blogs/item/307-fightingfor-our-provincial-fishbull-trout-in-the-tay-river https://naturecanada.ca/ news/blog/no-bull-nativetrout-threatened-inalberta/ https://cpawssouthernalberta.org/bulltrout-and-westslopecutthroat-trout/ https://raysweb.net/ specialplaces/pages/trout .html https://albertawilderness. ca/20191200_wla_listingab-native-fish-undersara/

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