In the warm and cozy cricket breeding room, thousands of crickets hatch every month. Those crickets serve as food for a variety of animals in the Zoological Garden, including many animals in research systems.

The animal keeper, Barak Levi, tends to the crickets professionally, meticulously, and with dedication, and closely follows the crickets' laying, hatching, and growing. In mid-December Barak noticed that the number of hatching crickets was dropping. A check revealed that a parasitic wasp that lays its eggs in cricket eggs had penetrated the cricket containers. The wasp's larvae develop faster than the young crickets, and therefore hatch before the infected crickets' eggs hatch. Most of infected crickets' eggs do not hatch at all. Within a short period the number of wasps had increased significantly and the crickets' growth began to be affected. Despite the drastic reduction in the number of hatching crickets, none of the researches or animals in the Garden were affected, thanks to our large reserves kept for such occasions. After consulting wasp experts from abroad, and Dr. Zoya Yefremova who works in the parasitic wasp collection in the Steinhardt Museum of Natural History, things did not look good. The turning point occurred when Dr. Yefremova told Barak that these wasps are active only by night. Armed with this knowledge, Barak deployed uncontaminated cricket containers in a separate room. In these containers Barak placed only cricket eggs that had been laid during day light hours; in other words, during the hours in which the wasps are not active. In other new containers he placed only sub-adult crickets that had not yet laid eggs and therefore were uninfected. In addition, Barak noticed that the wasps in the

infected containers live 10-12 days and then disappear; so, he threw away all the eggs that had been supposed to hatch during the days in which the wasps had been active and might have infected them. Barak also changed the sand that serves as bedding for the laying crickets and started to use more dense and compacted sand, in which the wasps find it difficult to reach the cricket eggs. He also covered the containers with a very dense mesh that prevented the wasps from penetrating them. After long days of careful and meticulous care the parasitic wasps have disappeared and the crickets' colony is clean once more.

Garden News