 Adult males are less ready to pursue and less efficient at catching than adult females , especially against larger prey . Males are quite effective against small web spiders , and reluctant to tackle large ones although they catch them in about 50 % of attempts . Against other jumping spiders , males do not pursue large ones and pursue about 48 % of small ones , catching 84 % of those they pursue . : 438 Males of Portia do not build large webs for catching prey ( " capture webs " ) . : 429 
