8 ms·

This study appears to be an alarmist rehash of what was previously discussed on HN: https://news.ycombinator.com/item?id=14323533 https://news.ycombinator.com/

This study appears to be an alarmist rehash of what was previously discussed on HN: https://news.ycombinator.com/item?id=14323533 https://news.ycombinator.com/item?id=14323533 Here's one of the original papers: https://www.farmlandbirds.net/sites/default/files/Orbrioch%20Nature%20reserve.pdf https://www.farmlandbirds.net/sites/default/files/Orbrioch%2... The 75% decline number appears to be from two data points from a 220-acre plot. From that paper: "What follows is a description of measured Insect-Biomasses from samples collected in the Orbroich Bruch Nature Reserve, near Krefeld, using Malaise Insect Traps. The results show that, in the same two areas, sampled in the years 1989 and 2013, there was a dramatic fall in the number of flying insects. Using the same traps, in the same areas, significant reductions of insect populations, of more than 75%, were found. Our data confirms, that in the areas studied, less than 25% of the original number of flying insects collected in 1989, were still present in 2013." "The Orboicher Bruch, to the Northwest of Krefeld, is a designated Nature Reserve of around 100 hectares (220 acres). Due to the reserve’s relatively remote location and its rugged landscape, intensive farming came to the area only recently." So alarmists are extrapolating from two data points (years 1989 and 2013) for a 220-hectare plot of German farmland to the entire world. I think that is a bit of a stretch, even for statistics. Since different bugs breed in different seasons, and numbers depend on the fruitfulness of previous generations, food supply, predation, disease, temperature and so on, this bug weight could vary considerably from year to year (or site to site) for any number of reasons. While one year cicadas thrive, the next year there may be none. BTW they're measuring the weight of dead bugs - not how many bugs or what species of bugs - just the weight of bugs. Actually they're not even measuring that, they're measuring the weight of dead bugs' soaked in 70-80% alcohol. I could go on and on about controls in statistical experiments but I think you get the idea. See the original HN posting for discussions pointers to the earlier papers.

b0rsuk 9y ago
If it makes you happier, these results confirms what me and my family simply see in an adjacent country (anecdotal evidence from several data points). There are barely any bugs. Mosquitos used to be a nuisance, everyone shared tips how to protect against them. You don't have to anymore, you can leave windows open at night. There was buzzing all over the garden, now you have to look close to spot a bug.
- delbel 9y ago
  anecdotal evidence from my pesticide free farm, this year I've had massive amount of bugs. Hundreds if not thousands of butterflies, massive house/horse fly problems, ant invasions, moths clogging up my plant propagator pumps, frog population explosion (there are now frogs in my office when people come visit me, they get "woken up" and I have to explain to them), massive bird population. Its 33f right now, and I see them flying around on my security camera system - so much I've had to disable the motion detection system the entire year because it is completely worthless even with the latest detection algorithm, with several cameras having massive spider webs because the bugs are attracted to the IR light. It could be a massive die off of bugs, but not here (Oregon).
  - canada_dry 9y ago
    > my pesticide free farm Well of course. I suspect insects of every type are now doing the equivalent of war-driving to find Monsanto free areas they can live.
    - VMG 9y ago
      Is this advertisement for Monsanto? Humans have been trying to get rid of pests for centuries, Monsanto didn't start it.
      - llukas 9y ago
        You're right, Monsanto didn't start it. They ended it.
      - cJ0th 9y ago
        That's like saying: Humans have fought each other with weapons since the beginning of time. Nukes are just another weapon...
    - u320 9y ago
      Monsanto is a herbicide vendor, not a pesticide vendor. Not everything you dislike about the ag sector is Monsantos doing.
sohkamyung 9y ago
I'm not able to access your link to the original paper (access problems on my end, possibly), but this write up on PlosONE [1] on the group's results seems to paint a different picture: Global declines in insects have sparked wide interest among scientists, politicians, and the general public. Loss of insect diversity and abundance is expected to provoke cascading effects on food webs and to jeopardize ecosystem services. Our understanding of the extent and underlying causes of this decline is based on the abundance of single species or taxonomic groups only, rather than changes in insect biomass which is more relevant for ecological functioning. Here, we used a standardized protocol to measure total insect biomass using Malaise traps, deployed over 27 years in 63 nature protection areas in Germany (96 unique location-year combinations) to infer on the status and trend of local entomofauna. Our analysis estimates a seasonal decline of 76%, and mid-summer decline of 82% in flying insect biomass over the 27 years of study. We show that this decline is apparent regardless of habitat type, while changes in weather, land use, and habitat characteristics cannot explain this overall decline. This yet unrecognized loss of insect biomass must be taken into account in evaluating declines in abundance of species depending on insects as a food source, and ecosystem functioning in the European landscape. [1] http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0185809 http://journals.plos.org/plosone/article?id=10.1371/journal....
wazoox 9y ago
This study confirms empirical observation all around. Insects are disappearing. Birds are disappearing (populations are down 50 to 60% for many species). Large animals are disappearing. Soils are disappearing. Fish are disappearing. The situation is quite obviously of imminent global catastrophe, but you can harp until the end about "alarmist predictions".
- gbog 9y ago
  Here on HN we need to back such affirmations with data. The bolder the affirmations, the more solid the data-backed proof need to be. If we were to exchange "philosophical" considerations here, I'd tell you that sunday fishermen have complained weekly that there was much more fish in the river before since the dawn of humanity. I'd also tell you that my own home in downtown Beijing has seen a slug invasion this year, and that these animals are not disappearing at all (at least in my courtyard).
  - JoeAltmaier 9y ago
    That's a symptom of ecological upset too. One species flourishing when another dies off, and the resulting wild cycles. Not a good sign.
    - gerbilly 9y ago
      Here's a good article on that topic: Planet of weeds Tallying the losses of Earth’s animals and plants By David Quammen/Harpers Magazine http://courses.botany.wisc.edu/botany_422/readings/Quammen1998.pdf http://courses.botany.wisc.edu/botany_422/readings/Quammen19...
  - soundwave106 9y ago
    Googling, a lot of the articles on species decline seem to point to the World Wildlife Foundation and The Living Planet, a survey published as a joint collaboration between the WWF and the Institute of Zoology. Obviously, there is probably some bias due to this being in part from a conservation advocacy group. However, the methodology does appear to be documented in a peer-reviewed paper [2]. So I'd personally give it a fair more weight than mere anecdote. [1] https://www.worldwildlife.org/pages/living-planet-report-2016 https://www.worldwildlife.org/pages/living-planet-report-201... [2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1569448/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1569448/
Quanttek 9y ago
This is just one preliminary "teaser" paper by the group, not the scientific paper published later that got so much media attention. Here it is: http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0185809 http://journals.plos.org/plosone/article?id=10.1371/journal..... Also, measuring the mass of dead bugs is an acceptable method to measure insect population (you then either have a decline of the number or the weight) and the decline has been consistent and constant as well as conforming other long-time studies. From their "methods and materials" section: > Biomass data were collected and archived using a standardized protocol across 63 unique locations between 1989 and 2016 (resulting in 96 unique location-year combinations) by the Entomological Society Krefeld. The standardized protocol of collection has been originally designed with the idea of integrating quantitative aspects of insects in the status assessment of the protected areas, and to construct a long-term archive in order to preserve (identified and not-identified) specimens of local diversity for future studies. In the present study, we consider the total biomass of flying insects to assess the state of local entomofauna as a group. > All trap locations were situated in protected areas, but with varying protection status: 37 locations are within Natura2000 sites, seven locations within designated Nature reserves, nine locations within Protected Landscape Areas (with funded conservation measures), six locations within Water Protection Zones, and four locations of protected habitat managed by Regional Associations. For all location permits have been obtained by the relevant authorities, as listed in the S1 Appendix. In our data, traps located in nutrient-poor heathlands, sandy grasslands, and dune habitats provide lower quantities of biomass as compared to nutrient nutrient-rich grasslands, margins and wastelands. As we were interested in whether the declines interact with local productivity, traps locations were pooled into 3 distinct habitat clusters, namely: nutrient-poor heathlands, sandy grassland, and dunes (habitat cluster 1, n = 19 locations, Fig 1A), nutrient-rich grasslands, margins and wasteland (habitat cluster 2, n = 41 locations, Fig 1B) and a third habitat cluster that included pioneer and shrub communities (n = 3 locations). > Most locations (59%, n = 37) were sampled in only one year, 20 locations in two years, five locations in three years, and one in four years, yielding in total 96 unique location-year combinations of measurements of seasonal total flying insect biomass. Our data do not represent longitudinal records at single sites, suitable to derive location specific trends (e.g. [28]). Prolonged trapping across years is in the present context (protected areas) deemed undesirable, as the sampling process itself can negatively impact local insect stocks. However, the data do permit an analysis at a higher spatial level, i.e. by treating seasonal insect biomass profiles as random samples of the state of entomofauna in protected areas in western Germany. > Malaise traps were deployed through the spring, summer and early autumn. They operated continuously (day and night), and catches were emptied at regular intervals, on average every 11.2 days (sd = 6.3). We collected in total 1503 trap samples, with an average of 16 (4–35) successive catches per location-year combination (Table 1). Between 1989 and 2016, a total of 53.54kg of invertebrates have been collected and stored, over a total trap exposure period of 16908 days, within an average of 176 exposure days per location-year combination. Malaise traps are known to collect a much wider diversity of insect species (e.g. [29–31]) as compared to suction traps (e.g. [28]) and are therefore considered superior as a method of collecting flying insects. On the basis of partial assessments, we can assume that the total number of insects included in 53.54 kg biomass represents millions of individuals. > The sampling was standardized in terms of trap construction, size and design (identical parts), colors, type of netting and ground sealing, trap orientation in the field as well as slope at the trap location. Hence none of the traps differed in any of these field aspects. Our trap model was similar to the bi-colored malaise trap model by Henry Townes [32, 33]. The traps, collecting design, and accompanying methods of biomass measurement as designed and applied by the Entomological Society Krefeld are described elsewhere [34–36] and in S2 Appendix. > Trap catches were stored in 80% ethanol solution, prior to weighing, and total insect biomass of each catch (bottle) was obtained based on a standardized measurement protocol by first subtracting fluid content. In order to optimally preserve samples for future species determination, the insects were weighed in an alcohol-wet state. First, the alcohol concentration in the vessels was stabilized to 80%, while this concentration was controlled with an areometer over a period of at least two days. In order to obtain biomass per sample with sufficient accuracy and comparability, the measuring process was fixed using a standardized protocol [34]. For this purpose the insects of a sample were poured onto a stainless steel sieve (10cm diameter) of 0.8 mm mesh width. This sieve is placed slightly obliquely (30 degrees) over a glass vessel. The skew position accelerates the first runoff of alcohol and thus the whole measuring procedure. The drop sequence is observed with a stopwatch. When the time between two drops has reached 10 seconds for the first time, the weighing process is performed with a laboratory scale. For the determination of the biomass, precision scales and analytical scales from Mettler company were used with an accuracy of at least 0.1g and controlled with calibrated test weights at the beginning of a new weighing series. In a series of 84 weightings of four different samples repeating this measurement procedure, an average deviation from the mean value of the measurement results of 0.4 percent was observed (unpublished results).

b0rsuk 9y ago

If it makes you happier, these results confirms what me and my family simply see in an adjacent country (anecdotal evidence from several data points). There are barely any bugs. Mosquitos used to be a nuisance, everyone shared tips how to protect against them. You don't have to anymore, you can leave windows open at night. There was buzzing all over the garden, now you have to look close to spot a bug.

delbel 9y ago
anecdotal evidence from my pesticide free farm, this year I've had massive amount of bugs. Hundreds if not thousands of butterflies, massive house/horse fly problems, ant invasions, moths clogging up my plant propagator pumps, frog population explosion (there are now frogs in my office when people come visit me, they get "woken up" and I have to explain to them), massive bird population. Its 33f right now, and I see them flying around on my security camera system - so much I've had to disable the motion detection system the entire year because it is completely worthless even with the latest detection algorithm, with several cameras having massive spider webs because the bugs are attracted to the IR light. It could be a massive die off of bugs, but not here (Oregon).
- canada_dry 9y ago
  > my pesticide free farm Well of course. I suspect insects of every type are now doing the equivalent of war-driving to find Monsanto free areas they can live.
  - VMG 9y ago
    Is this advertisement for Monsanto? Humans have been trying to get rid of pests for centuries, Monsanto didn't start it.
    - llukas 9y ago
      You're right, Monsanto didn't start it. They ended it.
    - cJ0th 9y ago
      That's like saying: Humans have fought each other with weapons since the beginning of time. Nukes are just another weapon...
  - u320 9y ago
    Monsanto is a herbicide vendor, not a pesticide vendor. Not everything you dislike about the ag sector is Monsantos doing.

sohkamyung 9y ago

I'm not able to access your link to the original paper (access problems on my end, possibly), but this write up on PlosONE [1] on the group's results seems to paint a different picture: Global declines in insects have sparked wide interest among scientists, politicians, and the general public. Loss of insect diversity and abundance is expected to provoke cascading effects on food webs and to jeopardize ecosystem services. Our understanding of the extent and underlying causes of this decline is based on the abundance of single species or taxonomic groups only, rather than changes in insect biomass which is more relevant for ecological functioning. Here, we used a standardized protocol to measure total insect biomass using Malaise traps, deployed over 27 years in 63 nature protection areas in Germany (96 unique location-year combinations) to infer on the status and trend of local entomofauna. Our analysis estimates a seasonal decline of 76%, and mid-summer decline of 82% in flying insect biomass over the 27 years of study. We show that this decline is apparent regardless of habitat type, while changes in weather, land use, and habitat characteristics cannot explain this overall decline. This yet unrecognized loss of insect biomass must be taken into account in evaluating declines in abundance of species depending on insects as a food source, and ecosystem functioning in the European landscape. [1] http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0185809 http://journals.plos.org/plosone/article?id=10.1371/journal....

wazoox 9y ago

This study confirms empirical observation all around. Insects are disappearing. Birds are disappearing (populations are down 50 to 60% for many species). Large animals are disappearing. Soils are disappearing. Fish are disappearing. The situation is quite obviously of imminent global catastrophe, but you can harp until the end about "alarmist predictions".

gbog 9y ago
Here on HN we need to back such affirmations with data. The bolder the affirmations, the more solid the data-backed proof need to be. If we were to exchange "philosophical" considerations here, I'd tell you that sunday fishermen have complained weekly that there was much more fish in the river before since the dawn of humanity. I'd also tell you that my own home in downtown Beijing has seen a slug invasion this year, and that these animals are not disappearing at all (at least in my courtyard).
- JoeAltmaier 9y ago
  That's a symptom of ecological upset too. One species flourishing when another dies off, and the resulting wild cycles. Not a good sign.
  - gerbilly 9y ago
    Here's a good article on that topic: Planet of weeds Tallying the losses of Earth’s animals and plants By David Quammen/Harpers Magazine http://courses.botany.wisc.edu/botany_422/readings/Quammen1998.pdf http://courses.botany.wisc.edu/botany_422/readings/Quammen19...
- soundwave106 9y ago
  Googling, a lot of the articles on species decline seem to point to the World Wildlife Foundation and The Living Planet, a survey published as a joint collaboration between the WWF and the Institute of Zoology. Obviously, there is probably some bias due to this being in part from a conservation advocacy group. However, the methodology does appear to be documented in a peer-reviewed paper [2]. So I'd personally give it a fair more weight than mere anecdote. [1] https://www.worldwildlife.org/pages/living-planet-report-2016 https://www.worldwildlife.org/pages/living-planet-report-201... [2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1569448/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1569448/

Quanttek 9y ago

This is just one preliminary "teaser" paper by the group, not the scientific paper published later that got so much media attention. Here it is: http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0185809 http://journals.plos.org/plosone/article?id=10.1371/journal..... Also, measuring the mass of dead bugs is an acceptable method to measure insect population (you then either have a decline of the number or the weight) and the decline has been consistent and constant as well as conforming other long-time studies. From their "methods and materials" section: > Biomass data were collected and archived using a standardized protocol across 63 unique locations between 1989 and 2016 (resulting in 96 unique location-year combinations) by the Entomological Society Krefeld. The standardized protocol of collection has been originally designed with the idea of integrating quantitative aspects of insects in the status assessment of the protected areas, and to construct a long-term archive in order to preserve (identified and not-identified) specimens of local diversity for future studies. In the present study, we consider the total biomass of flying insects to assess the state of local entomofauna as a group. > All trap locations were situated in protected areas, but with varying protection status: 37 locations are within Natura2000 sites, seven locations within designated Nature reserves, nine locations within Protected Landscape Areas (with funded conservation measures), six locations within Water Protection Zones, and four locations of protected habitat managed by Regional Associations. For all location permits have been obtained by the relevant authorities, as listed in the S1 Appendix. In our data, traps located in nutrient-poor heathlands, sandy grasslands, and dune habitats provide lower quantities of biomass as compared to nutrient nutrient-rich grasslands, margins and wastelands. As we were interested in whether the declines interact with local productivity, traps locations were pooled into 3 distinct habitat clusters, namely: nutrient-poor heathlands, sandy grassland, and dunes (habitat cluster 1, n = 19 locations, Fig 1A), nutrient-rich grasslands, margins and wasteland (habitat cluster 2, n = 41 locations, Fig 1B) and a third habitat cluster that included pioneer and shrub communities (n = 3 locations). > Most locations (59%, n = 37) were sampled in only one year, 20 locations in two years, five locations in three years, and one in four years, yielding in total 96 unique location-year combinations of measurements of seasonal total flying insect biomass. Our data do not represent longitudinal records at single sites, suitable to derive location specific trends (e.g. [28]). Prolonged trapping across years is in the present context (protected areas) deemed undesirable, as the sampling process itself can negatively impact local insect stocks. However, the data do permit an analysis at a higher spatial level, i.e. by treating seasonal insect biomass profiles as random samples of the state of entomofauna in protected areas in western Germany. > Malaise traps were deployed through the spring, summer and early autumn. They operated continuously (day and night), and catches were emptied at regular intervals, on average every 11.2 days (sd = 6.3). We collected in total 1503 trap samples, with an average of 16 (4–35) successive catches per location-year combination (Table 1). Between 1989 and 2016, a total of 53.54kg of invertebrates have been collected and stored, over a total trap exposure period of 16908 days, within an average of 176 exposure days per location-year combination. Malaise traps are known to collect a much wider diversity of insect species (e.g. [29–31]) as compared to suction traps (e.g. [28]) and are therefore considered superior as a method of collecting flying insects. On the basis of partial assessments, we can assume that the total number of insects included in 53.54 kg biomass represents millions of individuals. > The sampling was standardized in terms of trap construction, size and design (identical parts), colors, type of netting and ground sealing, trap orientation in the field as well as slope at the trap location. Hence none of the traps differed in any of these field aspects. Our trap model was similar to the bi-colored malaise trap model by Henry Townes [32, 33]. The traps, collecting design, and accompanying methods of biomass measurement as designed and applied by the Entomological Society Krefeld are described elsewhere [34–36] and in S2 Appendix. > Trap catches were stored in 80% ethanol solution, prior to weighing, and total insect biomass of each catch (bottle) was obtained based on a standardized measurement protocol by first subtracting fluid content. In order to optimally preserve samples for future species determination, the insects were weighed in an alcohol-wet state. First, the alcohol concentration in the vessels was stabilized to 80%, while this concentration was controlled with an areometer over a period of at least two days. In order to obtain biomass per sample with sufficient accuracy and comparability, the measuring process was fixed using a standardized protocol [34]. For this purpose the insects of a sample were poured onto a stainless steel sieve (10cm diameter) of 0.8 mm mesh width. This sieve is placed slightly obliquely (30 degrees) over a glass vessel. The skew position accelerates the first runoff of alcohol and thus the whole measuring procedure. The drop sequence is observed with a stopwatch. When the time between two drops has reached 10 seconds for the first time, the weighing process is performed with a laboratory scale. For the determination of the biomass, precision scales and analytical scales from Mettler company were used with an accuracy of at least 0.1g and controlled with calibrated test weights at the beginning of a new weighing series. In a series of 84 weightings of four different samples repeating this measurement procedure, an average deviation from the mean value of the measurement results of 0.4 percent was observed (unpublished results).