The main predators of the house martins are those birds of prey which are capable of catching these agile fliers, such as the hobby (Falco subbuteo).
Birds of the Delichon species are most vulnerable when collecting mud from the ground.
This has therefore become a communal activity, with a group of these birds descending suddenly on a patch of mud.
The generally insectivorous collared falconet has been recorded as hunting Nepal house martins.

The house martins are parasitised by fleas and mites, including the "house martin flea", Ceratophyllus hirundinis and its relatives.
A Polish study of the common house martin showed that nests typically contained more than 29 species of ectoparasite, with C. hirundinis and another swallow specialist, Oeciacus hirundinis, the most abundant.
The genus also hosts endoparasites such as Haemoproteus prognei (avian malaria), which are transmitted by blood-sucking insects including mosquitoes.

More than 40 beetle species have been recorded in common house martin nests, but most are either typical of the locality or found in the nests of other birds.
The typical number of individuals, around 200, is relatively low compared to other bird species (1,400 individual beetles for house sparrow, 2,000 for sand martin).
The beetles have no effect on the nesting birds, and the reason for their comparatively low numbers is unknown, although the numbers of specific parasites found in house martin's nests is also quite small.
The main predators of the house martins are those birds of prey which are capable of catching these agile fliers, such as the hobby (Falco subbuteo). Birds of the Delichon species are most vulnerable when collecting mud from the ground. This has therefore become a communal activity, with a group of these birds descending suddenly on a patch of mud. The generally insectivorous collared falconet has been recorded as hunting Nepal house martins.
The house martins are parasitised by fleas and mites, including the "house martin flea", Ceratophyllus hirundinis and its relatives. A Polish study of the common house martin showed that nests typically contained more than 29 species of ectoparasite, with C. hirundinis and another swallow specialist, Oeciacus hirundinis, the most abundant. The genus also hosts endoparasites such as Haemoproteus prognei (avian malaria), which are transmitted by blood-sucking insects including mosquitoes.
More than 40 beetle species have been recorded in common house martin nests, but most are either typical of the locality or found in the nests of other birds. The typical number of individuals, around 200, is relatively low compared to other bird species (1,400 individual beetles for house sparrow, 2,000 for sand martin). The beetles have no effect on the nesting birds, and the reason for their comparatively low numbers is unknown, although the numbers of specific parasites found in house martin's nests is also quite small.
Delichon