Herbivory - Science topic

I'm looking for papers/research on insect floral & seed herbivory on alpine thistles. However, I'm having trouble finding any information. Do you have or know of any papers that quantify the loss of flowers and seeds to inflorescence-feeding insects on HIGH MOUNTAIN (alpine) thistle species (especially CIRSIUM, CARDUUS)? Or any papers on this topic on ANY Asteraceae of the high alpine mountains?

I would appreciate ANY help you can give me - reprints I've missed (pdf), or references I should seek, or any clues to who might be doing this type of work.

THANK YOU! Svata Louda

Suppose there is a population of herbivorous species undergoing the rewilding phase. Following this stage, what steps should be taken to.

I'm interested in the earliest days of placental terrestrial locomotion in large herbivorous taxa. Phenacodus seems to be transitional in this regard. Any others?

Throughout the literature, it is unclear whether algal turfs (i.e. dense assemblages of short, turf-forming algae) are a form of algae that occurs due to the effects of disturbance (waves, herbivory) or if they represent a morphological advantage that has evolved over time.

With or without upwelling the copepoda Paracalanus quasimodo is present in high abundance in Cabo Frio. What would happen if this species was lost in the region, would the second most abundant species (Temora turbinata) take its place? Both preferentially herbivorous and highly related to the phytoplankton peaks present all year round.

Tropical grassy biomes, such as savannas, are often described as disturbance driven because of the important functions of consumers, namely fire and herbivory. When does a consumer shift from being a consumer to being a disturbance?

I'm looking for a protocol to apply simulated herbivory treatment on plants by spraying methyl jasmonate or jasmonic acid. If anyone has a detailed lab protocol to share that would be much appreciated!

I am also wondering, what is the difference between using MeJa or JA for the treatment? Is there any difference in terms of the expected response from the plant?

We will investigate the relationships between large herbivore movement and biodiversity. For this we need to track Oryx, Eland and Greater Kudu's. I am in contact with some companies (Lotek (UK), GPScollars (UK), African Wildlife Tracking(RSA), Vectronic (GER), Followit (SE)), but still would like to know if you have any recommendations for GPS collars for large herbivores in Southern Africa with irregular GSM-Network.

Thank you very much for sharing your expertise.

Equines as domestic herbivores and pack and riding animals face a serious challenge due to the expansion of rural road and motorized transport. What has to be done to keep their legacy in the smallholder farming systems?

Hi there! I am interested in understanding (or making myself more confused, whatever) the evolutionary pathways of coprophilic habit in dung-inhabiting fungi. Taking into account the dung of herbivore animals as a substrate to dung fungi growth, we have few "candidates" to be dung-producers with some requirements to early dung fungi (e.g. the amphibians Ichthyostega (I don't know if it was an herbivore or omnivorous, appearing about ca. 375 million y/a in Devonian, once the first tetrapod herbivores made their first appearance in the fossil record near the Permio-Carboniferous boundary, ca. 300 million y/a.). Terrestrial plants made their first appearance ca. 450 million y/a, with a well-accepted role of arbuscular mycorrhizal fungi in this process. So, my question is about if there is some study dealing with the evolutive process of dung-inhabiting fungi, presenting some consideration where and how, in the evolutive process, this ecologic habit firstly appears? Any considerations are welcome! Thank you!

As insects become more resistant to pesticides, the “smell of fear” some predators produce may someday be harnessed to repel and disrupt destructive insects naturally. In a recent study, a team of researchers found that the synthesized scent of a ladybug had measurable effects on their natural prey aphids in the lab, and the next step will be field tests. Plant-eating bugs pose threats to farmers and gardeners, prompting the use of pesticides. In the study led by Hermann, predator insects emit odors that their herbivorous prey can detect. This, in turn, changes pests’ behavior and even their physiology to avoid being eaten. The researchers have found a way to capture the “smell of fear” to obviate the need for harsh chemicals.

Farmers are known to use massive amounts of pesticides to get rid of the hordes of hungry insects that are destroying their crops because herbivores are a major threat to crop yields. These pesticides often cause massive environmental problems. They can reach our food, harm humans, threaten bees, kill birds, and destroy populations of predatory insects as well, making the crop pest problem worse in the long run. So one alternative that researchers and farmers have been testing is to use predatory insects to control plant-eaters. However, this approach - known as biological control - has its own challenges, as the release of many natural predators may not always target the intended species, in addition to the fact that some pests are invasive and have no native predators, and may even prey on each other in the end.

So, what is your scientific opinion on harnessing the natural smell of predators as a promising future direction of chemical ecology applied in sustainable pest control?

All comments and contributions are welcome.

Hi everyone,

I have 8 water quality parameters to explain the herbivory rate of sea urchins in seven different sites (80 observations in total). I have done a multiple linear regression and results showed that several parameters are significant drivers for herbivory rate.

I have also done an RDA on sea urchin abundance vs water quality (both multivariate) and visualized it, but somehow I am confused on how to visualize the herbivory (univariate) vs water quality. Is it still possible to do an RDA on this type of data? I understand I can make a residual plot of the regression, but I'm wondering if I could still have ordination arrows on the plot for herbivory vs water quality.

Many thanks, hope the description is clear enough to understand. I appreciate any feedback and suggestions.

I have camera trap data with its surrounding habitat quantification data.

I have above ground biomass values of fodder species of the certain area.

It occurs to me that nursery-grown plants (in the absence of herbivores) do not develop (inducible) defenses, and that when planted out, may suffer greater herbivore damage, at least initially. Does anyone have examples of this, or suggestions of it, from the literature?

Suppose, I want to study a grassland. I want to know what population size of herbivore of same or different species can sustain easily? What are the methodologies? What kind of precaution should be taken for this type of research? Is is possible to measure it's carrying capacity? Suggest me please. Thanks!

Need advice on feasibility and pitfalls associated with parasitological (molecular or traditional) testing of old fecal samples from animals (herbivores and carnivores). the samples range from 1-15 years in age. some preserved in refrigeration but most kept at RT in dry (hopefully) boxes.

I need to perform some assays of the relationship between the leaf area loss and the age of the leaf, but I have no experience with these. Do you have any idea?

Hi,

I've a big problem with analysing some field data of my master thesis. I recorded herbivory damage on plants in a transplant experiment along an elevational gradient with 30 different Brassicaceae species.

So I have 5 different sites at 5 elevations (600, 1000, 1400, 1600 and 2000 m). In each site, there are 30 different plant species with different elevational distribution (10 low-elevation, 10 mid-elevation, 10 high-elevation plant species), with 20 individuals per plant species = 600 individual plants at each site.

Each week from August 2018 until August 2019 I scored the herbivory damage on the leaves of all the plants with a scale from 0 to 5 (0= no damage, 1 = small feeding marks, 2 = <25% damaged, 3 = >25% damaged, 4 = >75% damaged, 5= completely eaten.

Now I'm trying to analyse my data but it is quite difficult.

I have these variables:

- taxa = plant species,

- elevation class = mid/low/high elevation class (or origin),

- site = 600/1000/1400/1600/2000

- damage score = values from 0 to 5 (ordinal variable)

- date of measure (date at which the damage was scored).

I add a printscreen of how data look like.

My main problem is that between all the variables, the number of observations changes, because some plants died or did not germinate (= different n obs between taxa, site and elevational class) or some sites could not been checked because of snow on the site (= different n obs between sites).

I would like to know if there is a way in R to standardize the number of observations across variables and across time.

I tried with the sample function and it works if I sample by site, taxa and elevational class. But I don't know how to sample also across time so that the sample is done all over the interval of time that I have for each site (e.g. when snow was there, the lowest sites could have been checked before the highest sites, so the date of measurements are variable between sites).

Is someone familiar with ordinal data and time series? Or could someone give me some insights about how could I simplify my data and my analyses?

Hope that you understood something about my question and I'm open to any kind of suggestion. Thank you in advance!

Cheers,

Janisse

One of my recent experiment refered to insect species, now the identification (to family level) has been done. In the following, I want to compare the differences in species richness and composition of insects between different treatments, which is easy. Besides, I also want to see the accumulative patterns of different functional groups (like herbivores vs. insect predators and pollinators vs. non-pollinators, or any other functional groups) in different treatments. However, I have few experiences in insect research and do not know how to identify which functional group an insect (family) belongs to. Does anyone know that? Are there some references or websites for such purposes?

I appreciate it a lot if anyone can give some suggestions.

Hi,

I am wondering if, regarding a single natural ecosystem, herbivores (or rhizophages) belowground are more generalists (in their diets), than aboveground herbivores? Would the soil complexity tends to promote low specificity of root herbivores? Do you know any papers dealing with this topic?

Thanks in advance for your feedback?

Best,

Matthieu

Assuming that u r a hardkeeper. you took 679 no. of animals to graze in the forest and field. using genetic analysis how can you group those animals? Lets say 19 animals are lost how can yo quantify them? Lets say there is an earthquake after 1 million years after, how can you say that how many animals are herbivores and howmany are carnivores? after 10 years of grazing the no. of species increased by 5 in no.s how?

Are there more efficient techniques available, rather than ImageJ, for quantifying herbivory damage from photos of leaves? I have a basic understanding of machine learning but don't want to spend too much time trying to learn another complicated technique.

Understanding the dietary requirements of a species is fundamental to its ex situ conservation.Green turtles are omnivores when young and become herbivores when they reach maturity, plant matter in the form of seaweed. Adult green turtles are herbivores, but in captivity the rescued turtles refuse to eat any other food, the primary food resource is not available , hence we are looking for preparing food resource which can help them to meet the nutritional requirement in their recovery from injuries.

Phytophagous insects take longer decision making time compared with specialist herbivore during their host selection process?

I am trying to sequence microbiome of flour beetles (16s) but due to the flour diet - most of the reads are chloroplast reads (more than 90%) So far only V1-V2 region was sequenced. I am still waiting for the results of V3-V4 region

Is there any way to remove chloroplast DNA during DNA extraction from insects? I have read about speficic primers that deal with this problem but at the moment I am trying to explore all the possibilites. Thank you!

Phytophagous insects take longer decision making time compared with specialist herbivore during their host selection? How

I am currently working on a project on herbivory and grasslands, but am unable to find proper review. Please help me in finding people who have done some sort of work in herbivory and grasslands management.

Best regards,

Shah

We are working on a project “Grazing damage on agricultural grasslands caused by large wild herbivores”. We would like to know “If and how the damage on grasslands caused by ungulate grazing is treated (if it is assessed and evaluated) in EU countries?” We are interested in methodologies to see if some of  them can be used also in Slovenia. Thank you, Ida

This is an exciting project! We work on vanilla planifolia plantations in North-Eastern Madagascar & we have made many observations of ants on vanilla harvesting extra-floral nectar. Our project is called "Diversity Turn in Land Use Science" and the ecologists of our project are currently assessing the biodiversity on vanilla plantations and alternative land-use types in order to define the value of vanilla plantations for conservation. Our PhD student focusing on ants has collected ants via baiting and pitfall trapping. However, the topic with vanilla-ant mutualism is still a mystery to us - however pre-studies are needed to define common pest. However, our vanilla pest damage shows so far, that herbivory is seemingly minor problem. Looking forward to find out more about your project!

I would like to calculate total amount of food that beetle larvae consume during larval stage. Unfortunately, they are soil dwellers by feeding on organic-matter rich soils. Feces can’t be distinguished from the food (soil). So, I used indirect methods to estimate their feeding performances.

I found that food retention time in the gut had linear relation with larval weight as:

R = 3W

where R is retention time (h) and W is larval weight (g)

and gut load (amount of food in larval body at a time) had linear relation with larval weight as:

L = 0.25W

where L is gut load (g) and W is larval weight (g).

The problem is beetle larval weight is not constant. It gradually increases over time. The growth of beetle larvae was varied in each individual and non-linear. Now, I have data about beetle growth for many individuals (the figure below is an example of the growth from one beetle). How can I estimate the total amount of food (soil) that each beetle eats during larval stage from these data?  

Thank you in advance.

Field observations or microscopical analysis have provided abundant results for decades. Besides, these geese often feed on just a few species, such as Cyperaceae, Gramineae. Is there any necessity to identify these food items at species-level, if the food spectrum is always so narrow?

I am doing herbivory experiments with T.ni caterpillars. I do have some susceptible and resistance plants variety. While arranging them in petriplate I think there should be some tricks. I mean patterns likewise suseptible should one side and resistance in other, or one by one?

Our study focuses on the impacts of grazing on hydrological processes, mainly surface runoff, evapotranspiration, and soil loss. We study different animals (with soft-padded feet and hooves) and different grazing intensities, and focus on mountainous areas in Peru. We found empirical evidence in many regions of the world, but not comprehensive review that could support a simple modeling approach.Thanks in advance!

Hello, 

I have been passed this photo of a small crustacean (Malacostraca?) eating planted mangrove seedlings (Rhizophora) in central coastal Vietnam. They are girdling the seedlings, which then fail. 

My knowledge does seem to be limited to: oh, looks like a sea louse (!), so I am asking the question.

The situation is somewhat brackish evidently, due to fluvial influence at that part of the estuary, and there is no herbivory in more saline  water plantings.

The picture isn't great, but hopefully enough. I do not expect there are easy solutions to the pest problem in mass reforestation efforts!

(Planted seedlings do seem to be generally more susceptible to herbivory and I do think, without visiting the site, that the mangrove species selection may be wrong here, but that is another topic!).

In the paper linked below a case study of a mason bee (Osmia bicornis) feeding on pollen is presented. We concluded that the growth and development and thus the fitness of the bee might be co-limited by the scarcity of N, K and Na in pollen. Cocoon production may be limited by a greater number of micronutrients. Since O. bicornis may experience limitations to the growth and development of its body and cocoon production because of the availability of certain elements in its food, the amounts of potentially limiting elements should be maximized during pollen collection by the adult female bee for its progeny.

Food nutritional quality is known to regulate populations of wild bees and may be a factor contributing to bee decline. In addition, specific micronutrients, especially Na and K, may be lacking in bee diets, thereby forcing bees to search for a balanced diet. The quality of the pollen diet has a known influence on the survival, physiology and life history traits of bees (of various taxa). These traits are all connected to fitness; therefore, pollen quality may influence bee foraging choices. Is it possible that the nutritional quality of pollen influences foraging behaviour and life-history traits of pollen-eaters? What do you think? 

I'm trying to find work on non-mammal vertebrate herbivores to find methods to assess their impacts on native vegetation. Is anyone familiar with studies on this issue? 

Hi everyone! Does anyone know about the herbivory/ovipository damage to plants that spider mites cause?- on a micro/molecular scale and on a whole plant basis. I am looking for literature or any kind of overview you can provide regarding the kind of damage that spider mites do to plants - both the kind of mechanical damage and the chemical if there is any. 

Thank you so much!

We need to compare our methodology and results of herbivory incidence in leafs of trees from three sucesional stages in tropical dry forests (early, intermidiate and late).

My colleagues are working on feeding preferences of macro symbionts of feather stars. They gathered data on stable isotopes from both sea lilies and its symbionts(shrimps, crabs, ,polychaetes, myzostomida etc). The results are quite surprising and not easy to interpret, so we want to have some reference points. Some people (who work with stable isotopes) advise us, that it might be more useful to collect data on primary consumers (not primary producents) from our area to have such a reference point.

But than we realized, that it is not an easy task to find really specialized primary consumer on the coral reef, as there is little known about food spectrum of most coral reefs inhabitant and many of them are mixotrophic.

We are interested in developing a new tool to quantify leaf herbivory, primarily by arthropods.  It will work from images taken of leaves in situ.  This will provide two advantages; leaves can be left in place without damaging the tree, and secondly it will allow for evaluation of damage over time.

We are currently doing a research on plant defense mechanism against caterpillar herbivory, and we would like to know if there are still possible ways to measure the effect of allelochemicals on caterpillars.

I have data consisting of seasonal transects of herbivore counts, which I wish to analyse using the kilometric abundance index. I want to determine how changes in prey abundance over the study period has affected demographic rates of various lion prides. I have used the outline of lion home ranges to divide the transects into transects per pride. However, due to seasonal changes in flooding and access to roads, some prides have more transects than others within each year. My main questions are:

1) How do I determine whether the differences in distance covered have a significant effect on the outcome of the kilometric abundance? And, if it does have an effect, how do I account for it?

2) I have both lean season and abundant season data for most years, but in two years have only abundant season data. If I want to use lean season data , how do I deal with the two years where I have only abundant season data?

I was watching a documentary from South Korea in which they are feeding domestic cats a vegan diet. I want to investigate if a vegan diet has negative impacts on carnivorous animals such as domestic cats.

I know of adult pest beetle (Popillia japonica and the mexican bean beetle) herbivory being negatively-affected by the treatment of leaflets with spider silk (Hlivko and Rypstra 2003; Rypstra and Buddle 2013). But I was wondering if there were any studies into pest species of Lepidoptera being affected.

Hello to everybody. My study is focused on host preference of sucking herbivorous arthropods and, in particular, how plant leaf structural traits affect the feeding choice of herbivores. The information on how herbivores penetrate leaf tissue with their stylets (physical or enzymatic way) can explain some correlations of their densities with leaf structural and mechanical properties. Herbivores involved in my study are scale insects and mealybugs, aphids, whiteflies, thrips, and spider mites.

I can't find papers on feeding/probing behaviour of spider mites and the way they penetrate plant tissues. I would be grateful if anyone could recommend some publications regarding this.

I was wondering whether in grasslands belowground herbivores are rather specific or generalist, and whether there are hypotheses stating that one or the other are more important for driving the assembly of plant communities. Any reference or idea is welcome!

I´m looking for a method to estimate plants biomass, maybe using plant cover? It is for understory species of a temperate forest under different silvopastoral practices.

I'm trying to detect if reptiles eat plants looking to their drops, but it is really difficult to see plant material using magnifying lens if they are digested. So, do you know if there is any dye to detect the presence of plant material in faeces of vertebrates? If so, is there a protocol available? Thanks!

I am interested in running a leaf palatability experiment on a group of related daisies to see if there are any interesting patterns associated with leaf type and herbivory. I thought I could purchase snails which would not have been exposed to the native daisies I plan to work with, however I could really do with some feedback. Has anyone run a cafeteria type experiment in which random leaf types are pinned to a grid? Are there any good methods/publications out there? I am also interested in the type of vector used or available. How time consuming (sorry the pun) can it be? And is it fraught with other issues I should be aware of?

This is not something I am at all accustomed to (as you have noted), but I would really like to give it a go.

Feedback welcome!

Wondering if somebody has quantitative data for observations on ants attacking herbivores and/or pollinators (as # observations/period of time) without any sort of manipulation. In other words, a person sits, observes, and records a natural predation event involving insects. There is interesting research on predation by (e.g.) spiders or ants, but it seems obvious that conclusions are mostly based on the results of removing the predator (either naturally not present in some plants, but present in others or experimentally removed) and measuring the effects of this onto a variety of plant features (involving vegetative growth or reproduction). Is this all what we have? Can anecdotal observations only be counted with one hand?