Question

please answer all three questions #9,10,11

bird grasshopper several plant species 09 What is the predicted effect of bird presence on the survivorship or biomass of the plants? (Hint: if this question leaves you puzzled, it may help to think about feeding time. If there were no birds, would more or less plant tissue be eaten by grasshoppers?) O 1. more birds results in decreased biomass O 2. more birds results in increased biomass O 3. fewer birds results in increased plant biomass Q10 If you want to protect the plants from insect damage, should you encouraged birds to forage on the plants, or put netting over the plants to keep birds out? Explain your reasoning Your answer

Answer 1

Question 9) option 2 is correct, more birds result in increased biomass.

In predator prey relationships, when predator is present it controls population of prey. So here birds are predators and grasshoppers are oey. Predators keep control of population of prey thus indirectly control foraging of grass by grasshoppers.  

Question 10) we will encourage birds to forage on the insect. This will keeps the no of insects in controlled no in turn protect plants from damage.

But if we put net , then this will prevent earing of insects by birds and increased foraging by insect.

Question 11) top consumer will directly affect the plants.

Top consumer lizard directly affect the no of spider and insectivores. Thus directly affect the biomass of plants.

Let's assume if lizard no deceased----' no of insects and spider increased--- increased foraging--- decreased biomass of plants.

Of lizard no increased--- less no of insects and spider -- less foraging-- increased biomass