Ågestasjön forms part of the Tyresån Lake System and, with a biodiversity unique in the Stockholm region, is highly popular among birdwatchers and ornithologists.

[2] Except for birdwatchers, the lake and its surrounding also attracts open-air lovers who use the area for walking, tour skating, and cross-country skiing.

[2] In 1998, a wide range of aquatic plants were documented in the lake: reed, common club-rush, common bulrush, lesser bulrush, yellow iris, alisma, branched bur-reed, water hemlock, marsh calla, water-soldier, yellow water-lily, white water-lily, broad-leaved pondweed, blunt-leaved pondweed, whorled water-milfoil, rigid hornwort, common bladderwort, pondweed, bog-bean, frogbit, lesser duckweed, greater duckweed, and ivy-leaved duckweed.

In contrast, perches show a small variation in scale, which is a sign of the lake being dominated by a single generation as individuals fail to reach carnivorous adulthood.

A presence of whooper swan dates back to 2004, while regular visitors include marsh harrier (2-3 couples), snipe, and Eurasian woodcock.

[2] There are a dozen couples of northern lapwing and eastern yellow wagtail, together with couples of meadow pipit, whinchat, red-backed shrike, bearded reedling, goshawk, spotted nutcracker, Eurasian wryneck, European honey buzzard, thrush nightingale, long-tailed tit, lesser spotted woodpecker, wood warbler, hawfinch, and Eurasian hobby.

Uncountable numbers of resting species are reported by the lake, including various swans, hawks, eagles, cormorants, and sparrows.