Two species of shorebirds are both adapted to live in coastal marshes. one species outcompetes the other for the small fish that live within one niche in the marsh. what is likely to happen to the other species of birds?

The population of other specie of birds will decline or other specie of birds will find some alternate source of food to survive.

Explanation:

According to the Competitive exclusion principle, which is also known as Gause's Law, two specie living in the same niche and feeding on the same resource cannot co-exist stably.

As we have well studied the theory of natural selection which states that only those organisms survive which have better tendency to compete for food and adapt to the environmental conditions.

Coming towards the question, what wi ll happen when One species outcompetes the other for the small fish , the other specie will not get enough food and will start to die or decline in population. Eventually either other specie needs to find another alternative food source for itself or migrate at some other location where there is less competition otherwise it will just not exist anymore at that niche.

Hope it help!

sheep is a herbivore animal whereas grasshopper belongs to the class chordates but both of them feed on greens.  

if grasshopper and sheep feeding on a pasture land, i do not think both of them will have any impact on each other. however, the number of the species can make difference. since sheep feed on greens, there is a possibility there left no pasture land for the grasshoppers or they may get extinct.

because they are eaten by the frog and the frog getseaten by the snake and the snake by the eagle