Workshop:

are the goals

and effects

clear?

Grazing in Coastal

Sand Dunes

8-10-2015

Harrie van der Hagen

Dunea, dune & water

2

drinking water for 1.3 mln people around The Hague

2400 ha of Natura 2000 coastal sand dunes

1 mln visitors per year

Dunea - drinking water & dune management

Are the goals for grazing clear?

At least maintaining biodiversity

Focus: quantity and quality of Grey Dunes (H2130)

By: replacing rabbits by large grazers (cattle, horses)

3

Are the effects clear?

Meijendel: low livestock grazing (0.07 LLU.ha.year)

Aerial photos 1975 – 1990 – 2001 - 2009: 3 landscape

zones, 50 ha grazed – not grazed per zone (PhD)

Livestock does not influence changes in sand & shrub (Hippophae)

Seedlings is rabbits pref.food: Hippophae rise and fall (mid 50’s –

1990); 85% Crataegus originates mid 1950’s (- 2150?)

Livestock maintains grasslands but changes quality: lichens are

overgrown by horizontale growing Agrostis, Carex arenaria increase

(‘badly’ eaten) and dominance of pleurocarp mosses

Soil compaction (dune grasslands become golf links) = lower

temperature: 3 weeks delay in insect larvae development4

Large Livestok Units

Livestock is not a cure for all ailments (European bison is?)

Once installed, do not stop this disturbance (Meijendel:

LLU lowered to 0.02/ha.year or part only winter grazing).

Rabbits: are crucial in maintaining dynamic dunes with

grassland mosaic (grazing, burrow digging, seedlings)

Rabbits up, livestock down. Statements:

1. We are/were better off without large grazers, also with

low rabbit densities (sand comes by it self)

2. start rabbit farming (and cut shrubs & trees)

5

Lessons learnt

Thank you