96 



WILD LIFE IN CALIFORNIA 



go into. When rather closely pressed I have 

 seen them take to the large, deep cracks in 

 adobe land. / 



The ground squirrels are a serious pest to 

 the farmers in many parts of the state, in that 

 they consume quite a percentage of the crops 

 before they can be harvested. They also 

 damage stock ranges in some sections by their 

 numberless burrows and by feeding on the 

 grass seeds. Government officials conducting 

 the war on the rodents have collected some 

 very interesting statistics in relation to this 

 matter. In sections of the state where they 

 had been operating for several seasons, they 

 secured statements of the owners of several 

 farms showing the gross receipts of farm prod- 

 ucts for a term prior to the beginning of the 

 attempt to exterminate the squirrels, and then 

 statements from the same farmers for the term 

 following or after the lands had been thor- 

 oughly cleared of the pests. The gain to the 

 farmers was surprisingly large and fully 

 demonstrated that they had been suffering 

 losses that could be obviated by exterminating 

 the squirrels. 



The genial climate of the Park district has 

 not been overlooked by insect life common to 

 our part of the country. Such orders as seem 

 adapted to the conditions here are generally 

 to be found well represented in large numbers. 

 As a consequence the grounds are at times 

 visited by various insectiverous birds. Flocks 

 of blue birds are to be seen at almost any hour 

 and nearly every day upon some part of the 

 fairway of the golf course. "What particular 

 insect, or insects, they feed upon I have, so 

 far, been unable to determine. Recently while 

 watching the actions of some of these birds 

 I saw a bird suddenly fly upward from the 

 ground in chase after a large locust or what 

 is commonly styled a grasshopper. The re- 

 markable thing about the incident was the 

 unusual height to which the insect flew and 

 its darting first one way and then another in 

 its effort to escape its feathered enemy. 

 Though the bluebird was quick on the wing 

 and closely followed the dips and turns of 

 the locust, the latter finally succeeded in 

 avoiding it and escaped. The actions of both 

 bird and insect seemed to be prompted by 

 something more than instinct. 



Species of what Fabre styles the Hunting 

 Wasps are very common in the park. One 

 of the most interesting of these insects be- 

 longs to the Pompilidae family, which 

 specializes on spiders as game. They are in- 

 teresting not only for their large size and 

 beauty, but their intelligent actions. Their 

 Jet black bodies with orange colored wings 

 and long legs give them a striking appearance, 

 frequently attracting the attention of people 

 not specially interested in insect life and 

 prompting them to inquire as to what they 

 are. After the sun has risen high enough 

 above the eastern horizon to give a temperature 

 agreeable to the wasps, a short walk in almost 

 any part of the grounds at the proper season 

 is almost certain to bring to one's notice one 

 or more of the big fellows either flying around 

 rather close to the ground or walking rapidly 

 about hunting for spiders. While observing 



the thoroughness of search they make for vic- 

 tims, under fallen leaves, in cracks and holes 

 in the earth, in bits of accumulated rubbish or 

 grass, omitting no place in which a spider 

 could hide, my mind would revert to the sim- 

 ilarity of their actions to those of a good pointer 

 or setter dog working among a bevy of quail 

 scattered and under cover in low brush, ferns 

 and rocks. Both show their eagerness in the 

 hunt, proximity of quarry and excitement that 

 follows by the manner of their agitating cer- 

 tain appendages. With the dog it is his tail, 

 with the wasp it is the antennae on the op- 

 posite end of the creature. 



The largest of this wasp family will attack 

 tarantulas, and nearly always succeeds in over- 

 coming the huge spiders, though sometimes 

 the latter becomes the victor, in which case 

 the tables are literally turned and the wasp is 

 served up as food for the winner. 



A very prettily marked wasp with slender 

 waist and lengthy legs that belongs to the 

 genus Sceiiphron is another spider hunter 

 that can be seen on warm days by anyone 

 who knows where to look for it. It will take 

 only a certain kind of small grass spider, 

 though spiders of other descriptions may be 

 more numerous. While I do not make this 

 statement as resulting from my own observa- 

 tions I can say I have examined a great many 

 nests of this wasp and I never found any 

 other than the little grass spiders in them. 



These wasps are the most common of our 

 "mud-daubers." Their nests constructed of 

 mud consisting of from three to a dozen cells 

 are ordinarily found about sheds and build- 

 ings in the country. I have watched them 

 build the nests admiring their mechanical 

 skill, especially when considering the paucity 

 of tools to work with. The work is wholly 

 done with their mouth parts aided by their 

 legs, particularly their front pair. The same 

 parts are used in gathering the clay or mud. 

 I found a place this summer that yielded the 

 kind of material the wasps wanted in the 

 construction of their nests, and I passed con- 

 siderable time on various occasions observing 

 their actions at the mud hole and their man- 

 ner of gathering the mud. Sometimes there 

 would be as many as five or six wasps in the 

 muddy depression. After selecting a spot 

 from which to dig up their loads the wasps 

 would scrape up the moist earth with their 

 mandibles, pushing it under their "chins" 

 where the stuff was held by the pair of front 

 legs until pellets as large or larger than goose 

 shot were accumulated. Apparently the 

 load was then seized with the mandibles, and 

 with the aid of the front or anterior pair of 

 legs carried away to the place where the cells 

 were being constructed. I think I was most 

 interested in the variation of the actions of 

 the different wasps in making selections of the 

 mud they needed. Some were quick to find 

 it, others took more time, while a few were 

 so particular that they ran all around the 

 depression, testing this place and that seem- 

 ingly being very difficult to satisfy. In the 

 meantime the first mentioned would make a 

 trip or two, as they returned directly to the 

 spot from which they had been taking the 



