[…] Spoiled of Orgallia's green domain, of wide Tir-Owen's woods, / Of high Tir-Conal's herdful hills and fishy-teeming floods; / Of all the warm vales, rich in goods of glebe-manuring men, / That bask against the morning sun along the Royal Glen.
Source: wiktionary
In addition to decreasing your odds of being the unlucky item on the big cat's menu, being in a herd also means that you can find out about impending danger much sooner than you would if you were alone. After all, a herdful of eyes is better than one measly pair.
Source: wiktionary