Increasing stocking success in alkaline lakes in British Columbia: characterizing the factors that affect high pH tolerance in rainbow trout

休闲钓鱼在加拿大是一项受欢迎的重要经济活动，在直接和间接经济活动中产生80多亿美元的收入，大约是加拿大商业渔业经济影响的五倍。仅在不列颠哥伦比亚省，每年约有40万名淡水垂钓者被吸引到不列颠哥伦比亚省的湖泊，为该省的经济带来了5.46亿美元的直接效益，并带来了4.11亿美元的间接和间接经济影响。不列颠哥伦比亚省淡水渔业协会（FFSBC）支持这一重要活动，每年在不列颠哥伦比亚省湖泊放养超过500万条鳟鱼。但是放养后的死亡率对FFSBC来说是巨大的经济成本。将鳟鱼放养在碱性（高pH值）湖泊会导致特别高的死亡率。目前，FFSBC的湖泊中约有四分之一具有高pH值，并且在过去几十年中，这些高pH值湖泊的数量及其pH值一直在增加。

Recreational fishing is a popular and economically important activity in Canada, generating more than $8 billion in both direct and indirect economic activity, which amounts to about five times the economic impact of the commercial fishery in Canada. In British Columbia alone, ~400,000 freshwater anglers are drawn to BC lakes annually contributing $546 million in direct benefits to the province's economy and $411 million in indirect and induced economic impacts. The Freshwater Fisheries Society of BC (FFSBC) supports this important activity by stocking BC lakes with over five million trout each year. But mortality following stocking can represent a substantial economic cost to the FFSBC. Stocking trout into alkaline (high pH) lakes results in particularly high mortality. At present, about one quarter of the lakes stocked by the FFSBC have high pH, and the number of these high pH lakes, and their pH levels, have been increasing over the last few decades.