ABSTRACT. The nighttime sky is increasingly illuminated by artificial light sources. Although this ecological light pollution is damaging ecosystems throughout the world, the topic has received relatively little attention. Many... more
ABSTRACT. The nighttime sky is increasingly illuminated by artificial light sources. Although this ecological light pollution is damaging ecosystems throughout the world, the topic has received relatively little attention. Many nocturnally migrating birds die or lose a large amount of their energy reserves during migration as a result of encountering artificial light sources. This happens, for instance, in the North Sea, where large numbers of nocturnally migrating birds are attracted to the many offshore platforms. Our aim is to develop bird-friendly artificial lighting that meets human demands for safety but does not attract and disorient birds. Our current working hypothesis is that artificial light interferes with the magnetic compass of the birds, one of several orientation mechanisms and especially important during overcast nights. Laboratory experiments have shown the magnetic compass to be wavelength dependent: migratory birds require light from the blue-green part of the sp...
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: This paper presents the topics discussed at the Proceedings of the contaminant mobility Working Group, various tables and charts, and a list of attendees. Discussed are the methods of contaminant measurement and pathways for spreading... more
: This paper presents the topics discussed at the Proceedings of the contaminant mobility Working Group, various tables and charts, and a list of attendees. Discussed are the methods of contaminant measurement and pathways for spreading contamination.
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: Mussels, Elliptio dilatata, were collected from a pristine lake and exposed in the Buffalo River, Lake Erie and a confined disposal site, Times Beach, Buffalo, New York. The mussels were exposed in a natural way, allowing them to burrow... more
: Mussels, Elliptio dilatata, were collected from a pristine lake and exposed in the Buffalo River, Lake Erie and a confined disposal site, Times Beach, Buffalo, New York. The mussels were exposed in a natural way, allowing them to burrow in the sediment or between stones. After a period of about 35 days the mussels were recollected and analyzed for PCBs, DDE and HCB. The Buffalo River was found to contain bioavailable PCBs and pesticides in three stretches only: 1) The two main branches, before they merge into the navigable stretch; 2) A stretch passing through several industrial estates downstream of Cazenovia Creek. This stretch is probably affected by an industrial discharge of a mixture comparable to Aroclor 1260; and 3) The mouth of the Buffalo River between the Marina and the Coast Guard Station. In Lake Erie, indications were found for a gradient in PCB concentration. Mussels exposed in Times Beach, were found to accumulate large amounts of lower chlorinated PCBs and pestici...
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: State of the art chemical analysis techniques were used for characterizing the contamination of dredged material, animal tissue, and water samples. This report provides tabular summaries of all analytical work carried out to date,... more
: State of the art chemical analysis techniques were used for characterizing the contamination of dredged material, animal tissue, and water samples. This report provides tabular summaries of all analytical work carried out to date, including concentrations of heavy metals and PCA and PCB in selected contaminated sediments and earthworm populations grown in the contaminated sediments. Sediment sources include Times Beach and adjacent Buffalo River, Bridgeport FVP, and Ottawa, Ill.
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: At Times Beach, Buffalo, N.Y., a prolific wildlife habitat has developed on a confined dredged material disposal facility. During 1983 studies were conducted to evaluate the availability of contaminants from the dredged material... more
: At Times Beach, Buffalo, N.Y., a prolific wildlife habitat has developed on a confined dredged material disposal facility. During 1983 studies were conducted to evaluate the availability of contaminants from the dredged material substrate to the animal community. The earthworm (Eisenia foetida) was used in growth chamber and field bioassay tests. After 28 days exposure the earthworms were harvested and analyzed for heavy metals, polyaromatic hydrocarbons (PAH's) and polychlorinated biphenyls (PCB's). Additionally, naturally occuring earthworms were collected from both the Times Beach site, and a reference site, and analyzed. The chemical analyses indicated significant accumulations of heavy metals, notably Cd and As; PCB's; and PAH's by the test and naturally occuring earthworms. The results of these studies were related to previously conducted plant bioassay and water quality studies at the site.
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The toxicity of condensate from the `Ameland` gasfield was compared to the toxicity of the standard North Sea oil `Forties`. The comparison was based on the `topped` (residue after distillation at 200 C) fraction. This fraction is... more
The toxicity of condensate from the `Ameland` gasfield was compared to the toxicity of the standard North Sea oil `Forties`. The comparison was based on the `topped` (residue after distillation at 200 C) fraction. This fraction is comparable with the fraction of the oil that is hazardous to the marine environment because the topped fraction will almost immediately evaporate. Hundred individuals of Corophium were placed in experimental systems with a surface of 500 CM{sup 2} filled with 10 cm sediment and 15 cm of water from the Wadden Sea. After two days the oil and condensate were added to the water surface in concentrations between 100 {micro}g/m{sup 2} to 100 {micro}g/m{sup 2}. After application a low tide was simulated until the oil or condensate covered the sediment. After five hours the sediment was inundated again. After three days the survival of the individuals and the remaining concentrations of oil and condensate in sediment were measured. From video images taken directly...
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: Aerially dispersed heavy metals from a high speed motorway have been shown to be entering an urban arboretum. Lead (Pb) and Cadmium (CD) were found as remote as 930 m from an east-west, multi-lane motorway. Both Pb and Cd were... more
: Aerially dispersed heavy metals from a high speed motorway have been shown to be entering an urban arboretum. Lead (Pb) and Cadmium (CD) were found as remote as 930 m from an east-west, multi-lane motorway. Both Pb and Cd were bioavailable to earthworms (Eisenia foetida) and both metals were more concentrated in surface soils than at depths of 1 meter. Seven sampling stations were established at progressive intervals along the 930 m transect. At all sampling stations, soil cores 15 cm deep and replicated four times were collected. The sod was removed from each sample except for one station 33 m away from the motorway. This was retained and tested along with some additional 1 m depth soil cores. All samples were transported to the U.S. Army Engineer Waterways Experiment Station (WES) where bioassay tests utilizing the earthworm (Eisenia foetida) were conducted under controlled conditions.
VER 60 MILLION BIRDS, OF MANY species, cross the North Sea twice each year. Light has a significant impact on migratory birds at sea as it can attract and trap birds at large illuminated structures such as offshore platforms. In this... more
VER 60 MILLION BIRDS, OF MANY species, cross the North Sea twice each year. Light has a significant impact on migratory birds at sea as it can attract and trap birds at large illuminated structures such as offshore platforms. In this article, we study the behavior of birds around offshore platforms and test the effect of the presence of lighting, the intensity and type of lights, and the light color on bird behavior. We developed a “bird-friendly” light spectrum that can be applied off-shore to provide safe lighting for both humans and birds. We present the results of a field demonstration test involving the exchange of lights to the new color on a gas production platform. We also demonstrate our sys-tem’s compliance with explosion safety requirements. It is expected that the bird-friendly lighting will become the new standard for any installation situated in areas
: Times Beach, the confined disposal site for dredged material at Buffalo, New York, was created in 1972 and used until 1976. The site was not filled to its full capacity, resulting in an upland, a wetland and an aquatic area, which were... more
: Times Beach, the confined disposal site for dredged material at Buffalo, New York, was created in 1972 and used until 1976. The site was not filled to its full capacity, resulting in an upland, a wetland and an aquatic area, which were rapidly invaded by plants and animals. By 1983, when studies were initiated, this invasion had resulted in established exosystems. The first studies were directed towards contaminant biomobility at the site and succession of terrestrial plant communities. This communication reports the occurrence of invertebrates in the aquatic portion of Times Beach and Lake Erie. The study is intended as a very general inventory for the purpose of finding groups of possible toxicological interest.
: The need for long-term predictive capabilities regarding contamination in waterways, dredged material, sediments, and soils is well recognized and is international in scope. The Proceedings of the Fifth International Workshop on... more
: The need for long-term predictive capabilities regarding contamination in waterways, dredged material, sediments, and soils is well recognized and is international in scope. The Proceedings of the Fifth International Workshop on Contaminant Mobility focus on three critical areas: the fate and effect of contaminants in the environment; physical, biological, and chemical assessment procedures; and regulatory decisionmaking criteria. The prediction of the environmental effects and fate of contaminants in dredged material has been based primarily upon bulk chemical analyses and bioassays of sediments collected prior to dredging and disposal operations. Dredged material changes greatly with time through physicochemical weathering (i.e., aging) processes such as drying, oxidation, photodecomposition, and leaching, especially when placed into an upland disposal environment. These processes are influenced further by the activities (i.e., bioturbation) of microorganisms, plants, and animal...
: Ten (10) European scientists evaluated research programmes in relation to contaminant mobility from dredged materials into ecosystems. Intensive investigations and inventories were conducted at the Times Beach confined disposal site,... more
: Ten (10) European scientists evaluated research programmes in relation to contaminant mobility from dredged materials into ecosystems. Intensive investigations and inventories were conducted at the Times Beach confined disposal site, which aided in the development of research objectives and future management concerns. Three Benton Harbor (ID) field sites were inspected, transects were lined out and sampling stations were selected. From each sampling station replicate soil or sediment samples were collected. Soil and sediments samples for an earthworm bioassay were collected from different depths representing the significant horizons that had been developed over time. A sampling station to collect background mussels for mussel watching at Times Beach was identified. Mussels were collected and exposed in Times Beach and Lake Erie. Mussels were also exposed at key locations in the Buffalo River in order to give an early warning to the District of future contaminant related dredging p...
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The difficulty of conducting bioaccumulation experiments with marine wetland animals in the laboratory is related to the need to establish intertidal conditions. In this study, a simple gravity-fed apparatus was constructed that allowed... more
The difficulty of conducting bioaccumulation experiments with marine wetland animals in the laboratory is related to the need to establish intertidal conditions. In this study, a simple gravity-fed apparatus was constructed that allowed the comparison of heavy metal, PCB and PAH-uptake by three bioassay species on 2 contaminated substrates. The ribbed mussel (Modiolus demissus), the mud snail (Nassarius obsoletus) and the sandworm (Nereis virens) were selected as bioassay organisms as these species are commonly found in disturbed wetlands and wetlands created with dredged material. Modiolus and Nassarius have not commonly been used as bioassay organisms as has Nereis. The test substrates (contaminated dredged material) came from the Interagency Field Verification of Testing and Predictive Methodologies for Evaluating Dredged Material Disposal Alternatives (Field Verification Program) field site in Bridgeport, CT. The source of the differences in the substrates is not of concern in this study as is demonstrating the feasibility of a simplified intertidal bioassay procedure.
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Between 1981 and 1986, the effects of oil pollution and the applicability of different oil spill combat methods in intertidal coastal waters were studied in large scale (20m2) experimental intertidal mesocosms (“OPEX”- project Kuiper et... more
Between 1981 and 1986, the effects of oil pollution and the applicability of different oil spill combat methods in intertidal coastal waters were studied in large scale (20m2) experimental intertidal mesocosms (“OPEX”- project Kuiper et al., 1983; Kuiper et al., 1986; Scholten et al., 1987). In these experiments North Sea oil (Forties) and fuel oil were tested, in various dosages. The most obvious effects were due to deposition of oil at the sediments during low tide. Small ostracods, together with the amphipods (mudshrimps and scuds) appeared to be the most sensitive species regarding oil pollution, followed by planktonic copepods, benthic bivalves (cockles and balthic tellins) and polychaete worms (Heteromastes sp. and Capitella sp.). The ranking of sensitivity of the exposed benthic species was not related to the oil type used. Moreover, the effect was clearly related to the dosage in ml.m-2.
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Freshwater and marine systems in the Netherlands are seriously polluted with inorganic and organic wastes discharged by several industrialized West-European countries into major rivers (Rhine, Meuse, Scheldt). Additional pollution results... more
Freshwater and marine systems in the Netherlands are seriously polluted with inorganic and organic wastes discharged by several industrialized West-European countries into major rivers (Rhine, Meuse, Scheldt). Additional pollution results from the dumping of chemical wastes and dredged materials in the North Sea.
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Contaminated sediments are often regarded as a nuisance, although not much is known about the effects of the contaminants on organisms exposed to them. High concentrations of contaminants in sediments are a general cause of concern. The... more
Contaminated sediments are often regarded as a nuisance, although not much is known about the effects of the contaminants on organisms exposed to them. High concentrations of contaminants in sediments are a general cause of concern. The problem becomes acute when large amounts of contaminated dredgings have to be disposed of. Harbor authorities worldwide are faced with the conflict between environmental concern on one hand and economical, feasible solutions on the other, a conflict that raises such questions as why and how sediments should be disposed of, what uses they can be put to, and how they should be treated (Tent 1984). Strangely enough we are far from answering the crucial questions in this context: whether the ecosystems living on top of contaminated sediments are “good” or “bad”, and whether disposal of contaminated sediments poses a threat to ecosystems elsewhere. Hardly any research has been done to answer these questions. This creates the incongruous situation where great efforts are being made towards solving the problem of transporting, confining and treating contaminated sediments when a sound ecotoxicological basis is lacking. This chapter summarizes and evaluates research attempting the basic question, whether, and if so, why, contaminated sediment poses a threat to the environment.
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Specific experiments that were performed with aquatic and terrestrial organisms have led to the conclusion that “bulk”; analyses are inadequate for the assessment of possible environmental risks. Furthermore, these experiments revealed... more
Specific experiments that were performed with aquatic and terrestrial organisms have led to the conclusion that “bulk”; analyses are inadequate for the assessment of possible environmental risks. Furthermore, these experiments revealed that only specific chemical forms are bioavailable, although information about the exact nature of these forms and the chemical processes involved often remained obscure. Based on this type of
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Artificial illumination on offshore oil and gas installations has a variety of effects on migratory and non-migratory birds, especially at night during foggy or overcast conditions. Birds attracted to platform lighting during the autumnal... more
Artificial illumination on offshore oil and gas installations has a variety of effects on migratory and non-migratory birds, especially at night during foggy or overcast conditions. Birds attracted to platform lighting during the autumnal migration can result in encirclement causing elevated avian mortality rates from bird strike, incineration in the flare (when the flare is in operation) and exhaustion. The problem has been documented for many years from areas as diverse as the North Sea, the Gulf of Mexico and Western Australia (Wiese et al., 2001). The impact of artificial light sources at night on migratory birds is a phenomenon not just linked to oil and gas platforms but also to other illuminated offshore and coastal structures such as wind farms, ships, harbors and lighthouses, all of which contribute to light pollution at night. Following several years of detailed observations, the Dutch E&P company NAM (Nederlandse Aardolie Maatschappij), established that conventional light...
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In the Dutch struggle against the sea a large dam (Enclosure dike) was built in 1932 closing off a coastal lagoon (fig. 1). This operation created a large freshwater body containing 5.5 km3 of water, mainly fed by the river Rhine. The... more
In the Dutch struggle against the sea a large dam (Enclosure dike) was built in 1932 closing off a coastal lagoon (fig. 1). This operation created a large freshwater body containing 5.5 km3 of water, mainly fed by the river Rhine. The estuarine ecosystem had disappeared within 3 years. Large amounts of contaminants are discharged in the lake and accumulate in sediments.
JW Simmers, GS Wilhelm, JM Marquenie, RG Rhett, SH Kay Environmental Management of Solid Waste: Dredged Material and Mine Tailings. Springer-Verlag, New York NY. 1988. ... (See also W89-05568) (White-Reimer-PTT) SW 3070 Water quality... more
JW Simmers, GS Wilhelm, JM Marquenie, RG Rhett, SH Kay Environmental Management of Solid Waste: Dredged Material and Mine Tailings. Springer-Verlag, New York NY. 1988. ... (See also W89-05568) (White-Reimer-PTT) SW 3070 Water quality control.
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From literature data it is calculated that on an annual basis, 11 to 17 tonnes of PCBs enter the North Sea. Largest sources are the Atlantic Ocean and the atmosphere: together they account for 60-79% of the total input. Sources with... more
From literature data it is calculated that on an annual basis, 11 to 17 tonnes of PCBs enter the North Sea. Largest sources are the Atlantic Ocean and the atmosphere: together they account for 60-79% of the total input. Sources with greatest impact are the rivers, sewers and sludge. Highest concentrations are found close to the Dutch shore and in the German Bight. The PCB levels result in adverse effects on the seal population in the Wadden Sea. Of the total world PCB production, at least 57% is still in use and their future dispersal into the oceans cannot easily be controlled. If the increase in ocean PCB concentration continues, it may ultimately result in the extinction of fish-eating marine mammals.
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The need for long-term predictive capabilities regarding contamination in waterways, dredged material, sediments, and soils is well recognized and is international in scope. The Proceedings of the Fifth International Workshop on... more
The need for long-term predictive capabilities regarding contamination in waterways, dredged material, sediments, and soils is well recognized and is international in scope. The Proceedings of the Fifth International Workshop on Contaminant Mobility focus on three critical areas: the fate and effect of contaminants in the environment; physical, biological, and chemical assessment procedures; and regulatory decisionmaking criteria. The prediction of the environmental effects and fate of contaminants in dredged material has been based primarily upon bulk chemical analyses and bioassays of sediments collected prior to dredging and disposal operations. Dredged material changes greatly with time through physicochemical weathering (i.e., aging) processes such as drying, oxidation, photodecomposition, and leaching, especially when placed into an upland disposal environment. These processes are influenced further by the activities (i.e., bioturbation) of microorganisms, plants, and animals....
... the first step was to gain insight into the extent of the problem by making ... North Sea and the Shell Expro and NAM operations 1989 Production figures Crude oil (103 m3 ... Possibly the contribution of other production chemicals,... more
... the first step was to gain insight into the extent of the problem by making ... North Sea and the Shell Expro and NAM operations 1989 Production figures Crude oil (103 m3 ... Possibly the contribution of other production chemicals, such as corrosion inhibitors, oxygen scavengers and ...
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ABSTRACT Gas exploration is expected to cause subsidence in the Wadden Sea. This in turn may have impacts on hydrodynamics, tidal geomorphology, benthic fauna, wading birds and salt marshes. This paper reports on two separate... more
ABSTRACT Gas exploration is expected to cause subsidence in the Wadden Sea. This in turn may have impacts on hydrodynamics, tidal geomorphology, benthic fauna, wading birds and salt marshes. This paper reports on two separate multidisciplinary studies: one predicting the longer-term effects of additional gas exploitation sites relative to sea level rise, and the other a longer-term verification monitoring at an existing site on the Wadden Sea island of Ameland. Both studies conclude that subsidence will cause local impacts on tidal flats, saltmarsh and dune geomorphology, on groundwater levels and inundation frequency of coastal marshes. The induced increased sediment needs, however, are small compared to those generated by sea level rise, and can be covered by present annual sediment fluxes unless sea level rise follows the most extreme IPCC scenario of a 100 cm rise in the coming century. The effects on the biota are insignificant compared to natural temporal variation.
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Over 60 million birds, of many species, cross the North Sea each year, twice. Light has a significant impact on migratory birds at sea, as it can attract and trap birds at large illuminated structures, such as off shore platforms. We... more
Over 60 million birds, of many species, cross the North Sea each year, twice. Light has a significant impact on migratory birds at sea, as it can attract and trap birds at large illuminated structures, such as off shore platforms. We first studied the behaviour of birds around offshore platforms and secondly tested the effect of the presence of lighting,
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Abstract In a joint Industry program, the composition and the environmental risk of produced water discharges on the Dutch Continental Shelf was investigated, along with the investigation of existing heavy metal removal technology... more
Abstract In a joint Industry program, the composition and the environmental risk of produced water discharges on the Dutch Continental Shelf was investigated, along with the investigation of existing heavy metal removal technology potentially suitable for offshore ...
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This group report gives an overview of applications of and issues in integrated assessment (IA) applied in the coastal zone area in Europe. We conclude that there are various reasons why IA is sometimes not successful. For instance,... more
This group report gives an overview of applications of and issues in integrated assessment (IA) applied in the coastal zone area in Europe. We conclude that there are various reasons why IA is sometimes not successful. For instance, integrated assessment tends to be ...
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Cadmium dosing experiments were carried out with the freshwater clam Unio pictorum in flow-through micro-streams in order to obtain additional information on the kinetics of cadmium accumulation and elimination. Accumulation of cadmium in... more
Cadmium dosing experiments were carried out with the freshwater clam Unio pictorum in flow-through micro-streams in order to obtain additional information on the kinetics of cadmium accumulation and elimination. Accumulation of cadmium in the kidney was rapid and within 3 weeks a concentration factor of 6000 was found. During elimination (29 weeks), the organs lose about one-third of their cadmium content rather rapidly, but no further elimination occurs. It can be concluded that the process of Cd accumulation is rapid and almost irreversible.
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The Clean Water Act in the United States requires that the environmental evaluation of dredged material prior to its discharge must include the effects of the proposed disposal environment on the bioaccumulation of contaminants in the... more
The Clean Water Act in the United States requires that the environmental evaluation of dredged material prior to its discharge must include the effects of the proposed disposal environment on the bioaccumulation of contaminants in the food chain. Although the total amount of contaminated material is relatively small when the national dredging program is considered, a significant effort is expended to ensure that, through the application of predictive tests prior to dredging, the contaminated material is deposited in a manner that will result in minimum contaminant mobility. There also has been a necessity to conduct studies and develop management plans in relation to the potential movement of contaminants at disposal sites constructed before the hazardous nature of many contaminants were known. Three case studies illustrate some of the bioassay and biomonitoring procedures currently being applied by the Corps of Engineers.
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ABSTRACT
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ABSTRACT Over 60 million birds, of many species, cross the North Sea twice each year. Light has a significant impact on migratory birds at sea as it can attract and trap birds at large illuminated structures such as offshore platforms. In... more
ABSTRACT Over 60 million birds, of many species, cross the North Sea twice each year. Light has a significant impact on migratory birds at sea as it can attract and trap birds at large illuminated structures such as offshore platforms. In this article, we study the behavior of birds around offshore platforms and test the effect of the presence of lighting, the intensity and type of lights, and the light color on bird behavior. We developed a bird-friendly light spectrum that can be applied offshore to provide safe lighting for both humans and birds. We present the results of a field demonstration test involving the exchange of lights to the new color on a gas production platform. We also demonstrate our systems compliance with explosion safety requirements. It is expected that the bird-friendly lighting will become the new standard for any installation situated in areas 56 with bird migration.
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The Dutch Wadden Sea island Schiermonnikoog revisited after 50 years. An analysis of change with as most likely cause for the vegetatational change the ammonia from the strongly increased dairy cattle farming. The change in morphology was... more
The Dutch Wadden Sea island Schiermonnikoog revisited after 50 years. An analysis of change with as most likely cause for the vegetatational change the ammonia from the strongly increased dairy cattle farming. The change in morphology was related to the closure of the former Lauwers Sea. This mobilized the vast amount of sand from the outer delta and made the island increase in length and in northerly direction.
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Na 50 jaar valt op dat vanaf de boot het Willemsduin, dat placht te blinken in het licht, niet meer zodanig herkenbaar is. Het lijkt geheel overwoekerd en vormt een dofgroene verhoging aan de einder. Na aankomst blijken ook de mooie en... more
Na 50 jaar valt op dat vanaf de boot het Willemsduin, dat placht te blinken in het licht, niet meer zodanig herkenbaar is. Het lijkt geheel overwoekerd en vormt een dofgroene verhoging aan de einder. Na aankomst blijken ook de mooie en soortenrijke weiden en slootkanten te zijn verdwenen en te
hebben plaatsgemaakt voor een eentonige vorm van akkerbouw, waarbij naast maïs, nu veel raaigras wordt verbouwd.
De koeien hebben hun horens verloren en staan of in de stal of staan
mistroostig met 100 lotgenoten op een kaal gemaaide raaigrasakker weidemelk te produceren.
De duindoorns staan meters hoog en het open dennenbos is overwoekerd met manshoge braamstruiken zonder bloem of vrucht. Ook de Kobbeduinen zijn onherkenbaar veranderd. De paarse helling met
wilgenroosje heeft plaatsgemaakt voor esdoorn en van de vlieren met judasoren stond er nog één bejaard exemplaar. Velden met korstmossen en open zand zijn verdwenen. Ook de konijnenpopulatie heeft het niet kunnen bolwerken in een overwoekerd landschap.
Dergelijke veranderingen zijn ook opgetreden op Ameland en Terschelling en zijn ingetreden in de periode 1975-1980. Na allerlei mogelijke oorzaken te hebben overwogen, lijkt de belangrijkste oorzaak toch de intensivering van de melkveehouderij.
Het eiland is ook van vorm veranderd. Het is langer geworden en breder met nieuwe duinenrijen. Het zand is vrijgekomen uit de buitendelta tussen Ameland en Schiermonnikoog ten gevolge van de afsluiting van de Lauwers zee. De verandering is verklaarbaar en maar tijdelijk. Door erosie van de buitendelta is het zand geland op de kust van Schiermonnikoog en zal uiteindelijk doorstromen naar het wad en oostelijk gelegen platen en eilanden, ter compensatie van zeespiegelstijging.
hebben plaatsgemaakt voor een eentonige vorm van akkerbouw, waarbij naast maïs, nu veel raaigras wordt verbouwd.
De koeien hebben hun horens verloren en staan of in de stal of staan
mistroostig met 100 lotgenoten op een kaal gemaaide raaigrasakker weidemelk te produceren.
De duindoorns staan meters hoog en het open dennenbos is overwoekerd met manshoge braamstruiken zonder bloem of vrucht. Ook de Kobbeduinen zijn onherkenbaar veranderd. De paarse helling met
wilgenroosje heeft plaatsgemaakt voor esdoorn en van de vlieren met judasoren stond er nog één bejaard exemplaar. Velden met korstmossen en open zand zijn verdwenen. Ook de konijnenpopulatie heeft het niet kunnen bolwerken in een overwoekerd landschap.
Dergelijke veranderingen zijn ook opgetreden op Ameland en Terschelling en zijn ingetreden in de periode 1975-1980. Na allerlei mogelijke oorzaken te hebben overwogen, lijkt de belangrijkste oorzaak toch de intensivering van de melkveehouderij.
Het eiland is ook van vorm veranderd. Het is langer geworden en breder met nieuwe duinenrijen. Het zand is vrijgekomen uit de buitendelta tussen Ameland en Schiermonnikoog ten gevolge van de afsluiting van de Lauwers zee. De verandering is verklaarbaar en maar tijdelijk. Door erosie van de buitendelta is het zand geland op de kust van Schiermonnikoog en zal uiteindelijk doorstromen naar het wad en oostelijk gelegen platen en eilanden, ter compensatie van zeespiegelstijging.