Janssen, G.M.

Leewis, L.

Rozema, J.

van Bodegom, P.M.

Open Marine Archive

Long term beach nourishment impacts in interaction with 
environmental factors on the abundance of four dominant intertidal 
macro invertebrate species  
Leewis Lies1, Peter M. van Bodegom1, Jelte Rozema1 and Gerard M. Janssen1,2 
1  Vrije Universiteit Amsterdam, Faculty of Earth and Life Sciences, Dept Systems Ecology, De 
Boelelaan 1085, 1081 HV, Amsterdam, the Netherlands 
E-mail: l.leewis@vu.nl 
2  Rijkswaterstaat, Centre for Water Management, Zuiderwagenplein 2, 8224 AD, Lelystad,  
the Netherlands 
 
Coastal squeeze is the largest threat for sandy coastal areas. To mitigate seaward threats  erosion 
and sea level rise , sand nourishments are commonly applied. However, its long term consequences 
on the macro invertebrate fauna  critical to most ecosystem services of sandy coasts  are still 
unknown. Seventeen sandy beaches  nourished and controls  were sampled in a chronosequential 
manner to investigate the abundance of four dominant macro fauna species and their relations with 
time since nourishment and relevant coastal environmental variables. Nourishments and 
environmental variables together explained the recovery of S. squamata, H. arenarius and B. sarsi. 
For E. pulchra, no environmental variable explained its abundance. Recovery took place within a 
year after nourishment. S. squamata even profited from the nourishments with increasing 
abundances after nourishment, taking into account its latitudinal gradient on the Dutch beaches. 
This confirms its role as an opportunistic species, therewith altering the initial community structure 
on a beach after nourishment. Beach nourishments do thus not seem to have long term negative 
consequences for the abundance of the four species. Responses to nourishments and 
environmental variables were species specific. This shows the importance of knowing the 
autecology of the sandy beach macro invertebrate fauna in order to be able to mitigate the effects 
of a beach nourishment and other environmental impacts. 
 
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Long term beach nourishment impacts in interaction with environmental factors on the abundance of four dominant intertidal macro invertebrate species

Results 
There was no effect of nourishment year on the 
individual species (fig. 2). Nourishment year 
explained only 1.74% of the community abundances 
(fig. 3). However, removing nourishment year from 
the analysis made the first axis insignificant. This 
suggests that the effect of nourishment year can 
only be detected when distributing the variance in 
species abundances across all relevant sources. 
Moreover, regression of the multivariate regression 
models’ residuals and nourishment year showed a 
nearly significant positive effect on S. squamata 
(table 1).  
RDA and multivariate regression showed that each 
species had different responses to the environment 
(table 1) and that latitude and morphological and 
sand characteristics were important (table 1 and 2). 
Long term beach nourishment impacts in interaction with 
environmental factors on the abundance of four 
dominant intertidal macro invertebrate species 
 
 Lies Leewis, Peter M. van Bodegom, Jelte Rozema, Gerard M. Janssen 
Coastal squeeze is the largest threat for sandy coastal areas, beaches  are trapped 
between sea level rise and coastal development. To mitigate the seaward threats - 
erosion and sea level rise, sand nourishments are commonly applied. However, its 
long term consequences on the beach macro invertebrate fauna are still unknown. 
We investigated the recovery times of four dominant intertidal macro invertebrates 
after beach nourishment and how their demands on their habitat modify their 
responses to beach nourishment. 
 
 
Sampling 
A chronosequence of 13 nourished and 4 
control (nrs. 2, 4, 10, 16) beaches was 
sampled (fig. 1), with 20 stratified random 
samples for fauna and sediment between 
MTL and MHW, and beach characteristics 
were recorded. 
Table 1 forward selection       year * residuals 
 *Log transformed Variable R2 P   R2 p 
S. squamata (ad.) Latitude 0,648 0,000   0,218 0,059 
S. squamata (juv.) Latitude + grainsize 0,648 0,001   0,164 0,107 
H. arenarius* SK + slope + latitude 0,833 0,000   0,009 0,717 
E. pulchra  -  -  -    -  - 
B. sarsi Sorting 0,414 0,005   0,001 0,893 
Getting in touch: 
lies.leewis@grontmij.nl 
 
Table 2 variance explained p 
latitude 24.9% 0.002 
sand skewness 8.1% 0.038 
slope 10.7% 0.058 
grainsize 7.4% 0.114 
Conclusions and management implications 
We found no negative long term consequences of beach nourishment on the abundance of the sampled species, and all 
species seemed to have recovered within one year. S. squamata even profited from beach nourishments, confirming its 
opportunistic nature. Previous studies focussed on species richness and total abundance, but we found responses to the 
environment to be species specific. This shows the importance of knowing the autecology of the macro-invertebrate 
fauna of a sandy beach to mitigate impact effects. Moreover, slope and sediment characteristics (including sorting and 
skewness) of a beach nourishment should be matched with the original beach. 
 
 
Figure 3. Redundancy Analysis (RDA)  
Figure 1. Sampled beaches 
Figure 2. Single regressions year - abundance 
Animal pictures by D. Tempelman and T. van Haaren                                  except for * by P. Tydeman, Rijkswaterstaat  
 
This research was funded by 


Long term beach nourishment impacts in interaction with environmental factors on the abundance of four dominant intertidal macro invertebrate species

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