Macroecology Blog - Hercos et al. 2012. Local and regional rarity in a diverse tropical fish assemblage. Proceedings of the Royal Society B.
October 11, 2018
Blog Author: Alex Shupinski
Authors:
Alexandre Pucci Hercos
Master's Degree in Zoology - Museu Paraense Emílio Goeldi (2006) and a doctorate in Freshwater Biology and Inner Fishing - National Institute of Amazonian Research. He studies the ecology of communities and focuses on ornamental fish of the Amazon.
H.L Queiroz
Conservation biologist who studies primates and fish behavior and works for the Mamirauá Institute for Sustainable Development. He focuses on the flood forests of the Amazon and managing the animal communities. He received his doctorate in 2000 from St. Andrews University, Scotland.
A.E. Magurran
She is a population biologist who was the advisor to Queiroz. She received her Ph.D. at the University of Ulster and her research focuses on the conservation of biodiversity.
Abstract:
-most of species richness are rare species
-tropical systems have high levels of rare species
-looking at diversity of freshwater fish in a series of Amazon lakes
-observe the relative abundance in the number of individuals and biomass to the occurrence of species in space and time
Intro:
-rare and common species are found in every community
-hard to prioritize rare species
-rare species are not always rare everywhere; abundance may be suppressed by local conditions
-distinguish the difference between species that are “rare throughout” and species that happen to be rare in a single locality
-Occurance – number of sites or samples that species is present in
-Prediction = mode for species that are infrequent in both space and time and a second mode will be detected of prevalent species in both space and time. It will be strongest at local scales
Methods:
-data collected from Brazilian Central Amazon floodplains
-5 different lakes were sampled monthly for two years between 2003-2005
-Fish were returned alive if possible or humanely euthanized if they could not be identified
-Rare species were considered to be any that were less than 1% of total individuals overall and categorized as “rare locally” or “rare throughout”.
Results:
-20,000 individual fish samples; 165 species, 99 genera, 29 families
-two modes were detected
-logistic regression indicates the less frequently rare species are more likely to be “rare throughout”
Discussion:
-found expected results that many species of fish in the amazon system are rare in abundance and biomass.
-species fall into the two clusters
-temporal and spatial occcurance are linked and can be used to deduce a species status
-can be used to address microbial systems
-biomass shows a unimodal distribution and close to lognormal
-abundance has an excess of low abundance classes with a asymmetric pattern
Thoughts:
I thought this paper was well-written and easy to read. The paper supports Hanski’s hypothesis and I think provides interesting results. I was caught off guard with the connection they tried to make with microbial communities and characterizing the “rare biosphere” but I wouldn’t mind diving deeper into the importance and application of this study to microbial communities.
I thought the paper was easy to read. However, figure 3 had a lot of stuff in one figure and was difficult to parse out. Another interesting thought is that the amount of rare species that they found. To me, there is this assumption that there are fewer rare species, and I've seen this in some of my own data. However in this paper, there seemed to be a high number of rare species in their data. Is this something that is common in tropical environments?
ReplyDeleteI agree with you on the connection with microbial communities. The author talks about how they are similar to fish communities without much explanation. It would be more helpful if they offer an example at lease.
ReplyDeleteWhen I first started reading this, I was confused how they were going to deal with ranges and migration of the “satellite” species since they were fish stuck in lakes. This is a really neat system to study fish in. The flooding period allows the fish a set period to move about and then the dry period essentially creates a perfect snapshot for ecologists to study! Way cool.
ReplyDeleteI wish Figure 3 also included the species that weren't found in any of the lakes, but were found in other parts of the reserve. Or were all species found in at least one lake? It was unclear.
ReplyDeleteI also would have liked more detail about the species of fish they found. They could have tied natural history or ecology of some of the species into their discussion. They list the dominant species in the results but never do anything with that information. There were also 37 species that were singletons, and it would have been interesting to read a bit more about some of these.
I liked this paper. I agree it was easy to read and I think their results are very interesting, as a another way to measure and analyze species that should be considered as endangered, or not. And it really a practical method that doesn't require much more than sampling and patience to count and identify species either by time or area scale. Have people taken into account this approach when applying conservation efforts in the last 6 years since this was published? Figure 3 was a bit confusing for me as well.
ReplyDeleteThis is one nice paper that is attempting to describe different categories of rare in their natural habitat. The general question and the application effort is great: which species to prioritize for conservation. My answer is that endemic species should be prioritized more than the dispersal rarity. The field choice is pretty clever because they have the data for the habitat fluctuation so they know exactly what causes these dispersals and when. I don't know why they use formalin first then alcohol for their preservation. Formalin kills genetic material. Over 20,000 fish collecting is impressive. It mentioned the microbial influence. This is a big factor that cannot be ignored. Great paper.
ReplyDeleteI agree with Willow that it is a very neat study system (and one extremely diverse). I wonder what happens at larger scales, the ‘rare throughout’ species in Mamiraua would be rare through their entire range?.
ReplyDeleteAlso, I liked that they analyzed their data using different definitions of local and through rarity, thus making their results more robust to the subjective definition of this categories.
Finally, I think is very interesting that although the abundance patterns matched the core-satellite hypothesis, the temporal data didn't show random changes in species abundance and occurrence. This contrast with the stochastic nature of Hanskis hypothesis.
This was my first time actually reading about microbiol... well anything. This was definitely a cool topic and it enhanced my understanding of paper 30. I'm curious to read any other papers that are similar to this paper.
ReplyDeleteInteresting to read the conservation implications from this paper. Considering the relatively recent publication, how's the current outlook on using this data to target conservation efforts?
ReplyDelete