Ages and lengths of Bull Trout from two Rocky Mountain lakes at two times.

Description

Assigned ages (from otoliths) and fork lengths of Bull Trout (Salvelinus confluentis) from two Rocky Mountain lakes in Alberta, CAN before and after a regulation change.

Format

A data frame with 96 observations on the following 4 variables:

• age: Age (from otoliths).

• fl: Fork length (mm).
• lake: Lake (Harrison and Osprey).

• era: Era of collection (1977-80 and 1997-01). See details.

Topic(s)

• Growth
• Von Bertalanffy growth model

Note

The historical (1977-1980) era samples were from before restrictive sportfishing regulatory regimes were implemented (in the 1990s) that led to changes in abundance and population structure of bull trout.

Source

From (approximately) Figure 2 of Parker, B.R., D.W. Schindler, F.M. Wilhelm, and D.B. Donald. 2007. Bull trout population responses to reductions in angler effort and retention limits. North American Journal of Fisheries Management, 27:848-859. [Was (is?) from https://www.researchgate.net/publication/233144141_Bull_Trout_Population_Responses_to_Reductions_in_Angler_Effort_and_Retention_Limits.]

Examples

data(BullTroutRML2)
str(BullTroutRML2)
head(BullTroutRML2)
op <- par(mfrow=c(2,2),pch=19)
plot(fl~age,data=BullTroutRML2,subset=lake=="Harrison" & era=="1977-80",main="Harrison, 1977-80")
plot(fl~age,data=BullTroutRML2,subset=lake=="Harrison" & era=="1997-01",main="Harrison, 1997-2001")
plot(fl~age,data=BullTroutRML2,subset=lake=="Osprey" & era=="1977-80",main="Osprey, 1977-80")
plot(fl~age,data=BullTroutRML2,subset=lake=="Osprey" & era=="1997-01",main="Osprey, 1997-2001")
par(op)