Concerning Tzphardea, Rabbi Hirsch 7 27 writes צפרדע can not mean crocodiles, otherwise there would have been no Egyptians left in the land. It is clear that they were only annoying creatures, not dangerous ones. Tradition has it that they were frogs.
How can he claim 'otherwise there would have been no Egyptians left in the land', they survived Arov, the mixed wild beasts? Is there any reason to assume they could survive Arov but not Tzphardea?
The Pesukim tell us that the Tzefarde'a went into their homes, bedrooms, bodies and even ovens.
וְעָלוּ וּבָאוּ בְּבֵיתֶךָ וּבַחֲדַר מִשְׁכָּבְךָ וְעַל מִטָּתֶךָ וּבְבֵית עֲבָדֶיךָ וּבְעַמֶּךָ וּבְתַנּוּרֶיךָ וּבְמִשְׁאֲרוֹתֶיךָ
There was no place in Egypt to hide from them, hence "no Egyptians would have survived".
The Arov did not have as much access:
הִנְנִי מַשְׁלִיחַ בְּךָ וּבַעֲבָדֶיךָ וּבְעַמְּךָ וּבְבָתֶּיךָ אֶת הֶעָרֹב וּמָלְאוּ בָּתֵּי מִצְרַיִם אֶת הֶעָרֹב וְגַם הָאֲדָמָה אֲשֶׁר הֵם עָלֶיהָ
It seems the Egyptians were able to hide in their bedrooms and protect themselves from the Arov.
