This is the narrow tidal stretch of water along the northern edge of Hilsea Lines. It
connects Langstone Harbour in the east to Tipner Lake and Portsmouth Harbour in the west.
Portsmouth is therefore on an island, and it is possible to take a boat all round. This is
not recommended since the tidal flows under the London Road bridge can be quite rapid.
Portscreek is significantly narrower than it used to be, as the construction of the A27 on
the northern side required the infilling of the mudflats. There is an interesting range of
birdlife, typically waders, gulls and some Brent Geese in the winter. Heron and Little Egret
are regular visitors. Look out for the blue flash of a Kingfisher.
The southern side of Portscreek at the eastern end still has some extensive
mudflats and associated plantlife. The colourful plants in the photo are Sea Lavender and Golden Samphire. Also present are Sea Purslane, Cord Grass and a few plants of Sea Wormwood.
Further west from here, the railway crosses onto Portsea Island, and was the area of the only
known colony of Shrubby Sea-blite in Hampshire. That was back in 1874.