Band‐tailed pigeons (Patagioenas fasciata) congregate at and use mineral sites (mineralized water or soil) throughout their range; however, information needed to interpret counts of pigeons at these sites and make inference to population abundance and distribution is lacking despite current monitoring efforts. Our objectives were to determine if we could create a mineral site used by band‐tailed pigeons; test whether pigeons seek supplemental sodium, calcium, or both; describe the pattern of pigeon use of mineral sites seasonally and within days by individual birds; and evaluate implications of precipitation, fog, temperature, and mineral concentration on pigeon visitation patterns. We attracted hundreds of pigeons/day to a created mineral site that offered sodium, calcium, or both in a forested area in southwestern Washington, USA where we captured and applied passive integrated transponder (PIT) tags to 771 pigeons and monitored mineral use during 2010–2014. When offered paired sodium and calcium stations, pigeons near exclusively consumed sodium, and pigeons continued to use the created mineral site for 3 years when calcium was not available. Pigeons visited sodium stations on average once every 12 days during June through early October; reducing available sodium concentration from 3,500 ppm to 1,000 ppm had no significant effect on visitation rates. Counts of pigeons at mineral sites varied with precipitation, sex, and time of season; consequently, comparison of pigeon counts among mineral sites can be biased if not accounting for these factors. Our results show that pigeons can be attracted to mineral stations, and that counts at mineral sites and stations allow opportunities for population monitoring. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

We examined growth in length of fluvial bull trout (Salvelinus confluentus) in the Walla Walla River Basin, Washington and Oregon. Our objectives were to quantify individual variability in growth; examine growth within and among years, life history forms, life stages and sexes; and estimate von Bertalanffy growth parameters. Individual variability was evaluated by modelling asymptotic length (L∞) and the growth coefficient (k) as random variables. All models were fit with Bayesian methods and were evaluated for fit by the deviance information criterion. By incorporating individual variability, population‐level estimates of L∞ and k appeared appropriate and estimated growth trajectories for specific bull trout fit individual observed patterns in growth. Growth trajectories and positive correlation between individual estimates of L∞ and k suggest that some individuals grow at a faster rate and reach a larger maximum size than other individuals and those differences are maintained throughout life. Selected models suggest that fluvial migrants have higher estimates of L∞ and k than residents, but there were only slight differences in parameter estimates among migrants from two adjacent spawning populations in the Walla Walla River Basin, as well as between males and females. Growth rates increased for fluvial migrants after subadult emigration. Individual variability in growth is consistent with the life history diversity assumed essential for bull trout population persistence. Quantifying this variability is important for modelling population dynamics and viability to conserve this threatened species.

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