The life cycle and natural diet of Cyrba algerina (Lucas) in the Apsheron Peninsula (Azerbaijan) was determined by sampling at frequent intervals throughout the year. Early-instar juveniles emerged in late July, grew to about half of adult size by winter, over-wintered and then, in the spring of the following year, grew to adult size and reached maturity. The primary mating season was in May, after which the number of adults in the population declined sharply. Ten arthropod orders were represented in the prey records from nature. Six of these were insects and four were arachnids. Spiders (order Araneae) were the dominant prey, accounting for 56% of the records. Half of these spiders were from one family, Oecobiidae. In laboratory prey-choice tests, C. algerina selected spiders in preference to insects and selected oecobiids in preference to other spiders. Video taping under infrared light confirmed that the Azerbaijan C. algerina captures prey in complete darkness.

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In laboratory experiments using lures (dead spiders in lifelike posture), six salticid species from four genera (Brettus, Cocalus, Cyrba, and Portia) are shown to use an opportunistic smokescreen tactic, comparable to a tactic previously demonstrated in Portia, in experiments using living prey instead of lures. After invading webs of other spiders, each of these species exploits situations in which the resident spider's ability to detect the predator's approach is impaired: periods when the web was being blown by a fan (simulating wind) or shaken by a moving magnet attached to a cork (simulating struggles of an insect ensnared in the web). When stalking a spider, each species moved significantly farther during intervals when disturbances (i.e., simulated wind or simulated insect struggles) were present than during intervals when no disturbances were present. However, when oriented toward an ensnared insect in the web, when already feeding on a spider, or when in a vacant web with no prey spider in view, there was no evidence that the salticid timed locomotion to correspond with the presence of disturbances, suggesting that the behavioural reaction recorded is reserved specifically for occasions when the salticid is oriented toward prey spiders in webs.

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