 A Portia can pluck another spider 's web with a virtually unlimited range of signals , either to lure the prey out into the open or calming the prey by monotonously repeating the same signal while the Portia walks slowly close enough to bite it . : 340 – 341 Such tactics enable Portia species to take web spiders from 10 % to 200 % of a Portia ′ s size , and Portia species hunt in all types of webs . : 491 In contrast , other cursorial spiders generally have difficulty moving on webs , and web @-@ building spiders find it difficult to move in webs unlike those they build . When hunting in another spider 's web , a Portia ′ s slow , choppy movements and the flaps on its legs make it resemble leaf detritus caught in the web and blown in a breeze . : 514 P. fimbriata and some other Portia species use breezes and other disturbances as " smokescreens " in which these predators can approach web spiders more quickly , and revert to a more cautious approach when the disturbance disappears . : 313 A few web spiders run far away when they sense the un @-@ rhythmical gait of a Portia entering the web – a reaction Wilcox and Jackson call " Portia panic " . : 418 
