Puszcza Piska Forest
... that the most valuable biosphere reserve in Poland's Puszcza Piska Forest is home to the Mute Swan , which arrives in numbers reaching up to 2,000 birds in time of moult?
... that the most valuable <a class="mw-redirect" href="./Biosphere_reserve" id="mwHNQ" rel="mw:WikiLink" title="Biosphere reserve">biosphere reserve</a> in Poland's <b id="mwHNU"><a href="./Puszcza_Piska" id="mwHNY" rel="mw:WikiLink" title="Puszcza Piska">Puszcza Piska Forest</a></b> is home to the <a class="mw-redirect" href="./Mute_Swan" id="mwHNc" rel="mw:WikiLink" title="Mute Swan">Mute Swan</a> <i id="mwHNg">(pictured)</i>, which arrives in numbers reaching up to 2,000 birds in time of <a href="./Moulting" id="mwHNk" rel="mw:WikiLink" title="Moulting">moult</a>?