![]() ![]() These results, together with limited evidence from the literature, suggest a highly interconnected food web with several modules, in which similarly sized predators from the same microhabitat are likely to compete strongly for resources in the field (observed Pianka’s diet overlap indices >0.85). Modularity analysis separated all primarily nectonic predator and prey species from two groups of large and small benthic predators and their prey. Diet overlaps between all predator pairs and predator overlaps between all prey pairs were non-zero. ![]() ![]() The predators most often preferred dipteran larvae previous studies further reported preferences for cladocerans. All predators in our experiments fed selectively on the seven prey species offered, and vulnerability to predation varied strongly between the prey. We conducted multiple-choice predation experiments using nine common species of predatory aquatic insects, including adult and larval Coleoptera, adult Heteroptera and larval Odonata, and complemented them with literature survey of similar experiments. Knowledge of their diet composition is fragmentary, which hinders the understanding of mechanisms maintaining their high local diversity and of their impacts on local food web structure and dynamics. Anyway night fell, I didn’t have a torch and so I ended up leaving some sticks in it’s vicinity and hoping it would find them….I will check in the morning.Predatory aquatic insects are a diverse group comprising top predators in small fishless water bodies. I didn’t want to handle it because firstly let’s face it, it is an enormous insect with lots of legs that tingle unpleasantly on your skin as it moves, and they move very fast, and secondly aI didn’t want to damage it. I tried to assist but unfortunately the nymph wasn’t having it. The nymph struggled to find purchase, swimming pool edges are not very good to hold onto, and the last nymph that didn’t climb high enough ended up being damaged. And had the pleasure of watching them leap into their new home: And tonight as I went down into the pool again to check the last of the water still in there and to see if I could save any other errant creature, I had the pleasure of observing as a dragon fly nymph swam to the edge, crawled out and then starting looking for somewhere good to hold onto to suspend itself in preparation for exiting the exoskeleton. I spent a wonderful morning wading in wellie boots through the sludge, the result of many years of autumn leaves rotting in what was left of the water one year. And I feel bad that I didn’t get them all…. I spent many hours stomping through the water trying to find animals – a sisyphean task. It’s hard having to empty out a pond that is in the height of it’s cycle – the water, teeming with life, looks like primordial soup, and as we emptied it out for the first time in not living but at least conscious memory we felt we had a duty to its current inhabitants. And then there were dragon fly nymphs and lots of small insects. The pool that I took the animals from has gone for many years of not being used and has in the interim become a very large garden pond, complete with newts and all kinds of insects and frogs – green ones that survived the fact that they couldn’t get out once they’d got in, and paler white ones that drowned. ![]() GOING GOING GONE II – WHEEE – this newt plunged right in, was great to watch – sadly I was holding the bucket in one hand, the camera in the other and balancing on the edge of a pone on some rocks – so focus off, but still love the picture for what it represents Going going GONE – yep the new pond looks like a good place to be! Some were set free under a hedge (the frogs were carried round the corner and set free behind a neighbour’s garden (she has a pond…) The dragon flies are still in the water and the newts were moved to a new pond: Alpine newt getting ready to enter his new home a friendly happy neighbourhood pond In the past posts I have been sharing what I have learned about the creatures I had the pleasure of saving from the swimming pool. ![]()
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