Aggregation of whelks, Buccinum undatum, near feeding predators: the role of reproductive requirements.

In the Mingan Islands, northern Gulf of St Lawrence (eastern Canada), the whelk Buccinum undatum displays a strong escape response to its predator, the asteroid Leptasterias polaris, nevertheless large sexually mature individuals occasionally approach feeding L. polaris to obtain food. In this study, we investigated the hypothesis that reproductive requirements increase the tendency of sexually mature whelks to approach feeding asteroids.

Impact of a castrating trematode, Neophasis sp., on the common whelk, Buccinum undatum, in the northern Gulf of St. Lawrence.

We observed heavy trematode infections of whelks, Buccinum undatum, from the Mingan Islands, eastern Canada, by larval stages of a species of Neophasis. Only sexually mature whelks were infected, 23% of mature females and 15% of mature males, and prevalence increased rapidly with whelk size. In most cases the parasite completely occupied the gonad, causing castration.

A comparative study of the chemical stability of various mitomycin C solutions used in glaucoma filtering surgery.

Objective: To determine the chemical stability of various mitomycin C (MMC) solutions used in glaucoma filtering surgery.

Methods: A survey of the MMC solutions currently in use in 21 hospitals (11 in Canada, 10 in the United States) was conducted. A comparative study of the chemical stability of five different representative solutions was performed.