Make it a strong brew and have a couple of spare match sticks at the ready! :0)
When it comes to wasp feeding behaviour it's important to appreciate that adult wasps ostensibly feed on carbohydrates which is not surprising given the energy that they burn in flight. The only thing that changes is the source of that carbohydrate. When queen wasps come out of hibernation the only natural source of carbohydrates in spring of note is nectar. So queen wasps are pollinators until such time as they start their nests and have larval brood. Much like honey bee larvae, wasp larvae require protein to develop. Unlike honey bee larvae, that protein source comes primarily from other insects. Interestingly, the exoskeletons of insects are made from chitin (linear polymer of n-acetylglucosamine) which is a rich source of glucose. When wasp grubs are fed insects they digest the protein and fats to grow and convert chitin from exoskeletons into sugar which they regurgitate and trophallactically feed to adult wasps as a reward for being fed by them. This feeding symbiosis between adults and grubs and vice-versa is a strong driver of wasp behaviour. Essentially adult wasps will focus on hunting insect prey whilst there is still brood in the nest because the trophallactic feed they receive from their grubs is optimized for their needs i.e. highly concentrated meaning low volume high energy intake. Biologically this is critical because low carbohydrate liquids such as fruit juices require significant intake of fluid for the same calorific intake making wasps heavier and less capable in flight. Hunting insects requires nimble fast flight and therefore high quality low weight food. If a wasp is tanked up with liquid it cannot lift the same prey load which inhibits colony development. That's why wasps during the hunting phase of their life cycle largely ignore other less optimal carbohydrate food sources and focus on hunting.
There will be occasions when wasps will turn to carbohydrates during the hunting phase of their life cycle. One of the most common reasons for this is if they no longer have access to their nests to get carbohydrates via trophallaxis, i.e. when their nests have been destroyed. Nest eradication especially by pest controllers during the hunting phase of the wasp life cycle is responsible for generating premature wasp sweet feeding behaviour. Experience has shown that proactive nest eradication programmes at outdoor attractions such as theme parks and zoos generates significant risk to patrons because of the premature creation of sweet feeding nuisance wasps. Those same wasps will also be attracted to hives. Wasps will also turn to sweet feeding to supplement their diet if there is insufficient insect prey available to feed their brood. When such starvation happens there is heightened risk of cannibalization of wasp nests by other wasps as well as heightened risk of hives being predated for protein. Interestingly, Asian hornets display this type of feeding behaviour in temperature dry zones where there is insufficient prey to sustain them. Because they are a large insect they require substantially more insect prey to support their brood and they are not always able to get sufficient insect prey. That's one of the reasons why Velutina can be found feeding on high nectar bearing plants throughout the hunting season. Finally, there comes a time when wasp nests mature when the sexual progeny is released. When this happens the incumbent queen stops laying eggs and the brood dries up. Wasp nest maturation is characterized by a crescendo of protein feeding as the sexual brood matures and then a switch to sweet feeding as the remnants of the brood develop and pupate denying adults carbohydrates from within the nest. This cross over period may last a few days where some wasps will continue to hunt to feed the rump of the brood whilst other wasps start sweet feeding because there isn't enough brood left to feed them.
When wasps sweet feed after nest maturation, behaviour around the nest changes dramatically. Wasps no longer return to the nest as frequently as they did during hunting because they spend more time away feeding themselves. They do periodically return to the nest to trophallactically feed the queen and the sentries but otherwise the nest becomes largely moribund (except at evenings when they come back to roost). This has the effect of inhibiting nest mate recruitment to food sources because there aren't the same number of resident wasps during this period. Whilst recruitment may take a little longer it is nevertheless still competent when it happens. Wasp recruitment has been dismissed by many authors who compare it to that of honeybees without understanding nest dynamics. Honeybee hives comparatively speaking remain heavily populated making recruitment to food sources a much more tangible process. Wasp nest recruitment is no less competent but because wasp nests might only have circa 5% resident population at any one time during sweet feeding, there aren't the numbers of wasps present to recruit at scale so recruitment is understandably slower. Nevertheless wasps do recruit their nest mates to sweet food sources.
When it comes to sweet feeding wasps follow a certain pattern of behaviour depending on the nature and quality of the food source. If the food source is a residual food source, i.e. the solitary wasp is unable to consume the food itself, it will return to the nest to recruit nest mates. It does this because that residual food source will attract wasps from other colonies and wasps compete aggressively (but not mortally) for sweet foods away from their nests. A solitary wasp stands little chance of consuming a sweet food if that food is being protected by a team of wasps from another colony. The only way it stands a chance is by recruiting fellow nest mates so that together they stand a chance of beating off the competition. This behaviour gives rise to scouting where solitary wasps look for food followed by 'swarm' feeding to protect that food from other wasps. Team feeding is probably a more apt description because the numbers at any given food sources may range from half a dozen nest mates to a few hundred - not the thousands associated with most people's image of a swarm. That said, if several nests are contributing wasps to a quality food source then it can rapidly become thousands of wasps. Sugar refineries are good examples of where this happens. The other thing to appreciate is that wasps have remarkable powers of navigation and will navigate to within millimeters of where they found a food source and they will keep returning to that same food source until it is consumed. I term this 'programmed feeding' because wasps are 'programmed' to continue feeding at the same food source until it has disappeared and they will do this ignoring all other food sources. The only way in which programme feeding wasps will turn to an alternative food source is if their access to the original food source is interrupted.
An example of this is where wasps find and overwhelm a hive. If that hive is moved, wasps will continue to return to the exact location of the original hive. If those wasps are not eradicated they will migrate to find alternative food sources which might be the next hive in the apiary. The best way to combat this is to place a trap in the exact location where the hive was before it was moved. That way the wasps will find the trap and provided the trap is a high efficiency trap the wasps should virtually all be eradicated. Use of low efficiency traps will simply perpetuate a background population of wasps in the vicinity of the trap until the trap ceases to be a food source and the wasps migrate elsewhere.
The majority of sweet food sources for wasps follow the pattern of scouting wasp finds food, recruits nest mates who swarm feed and they continue to programme feed by returning to the same food source (within millimeters) until it is consumed. This applies to hives but where hives differ is that honeybees and beekeepers will act to defend honey stores. Where the defense of these stores results in wasps being maimed and killed (especially where beekeepers squash wasps on the actual hives) the wasps coat the hives with distress pheromones as a consequence. These alarm pheromones drive wasps potty drawing them in from miles around. The result is what I term 'frenzied' feeding by a massive onslaught of wasps - quite distressing to observe and very loud to boot. Simply moving a hive coated in alarm pheromones won't work because those pheromones create an overwhelming draw for wasps no matter where the hive is moved to. In such a situation the best way to save the hive is to move the colony into a clean new hive (crack of dawn just before wasps start flying in earnest) and leave the old pheromone contaminated hive in place with a trap placed on top of it. The alternative is as previously stated to wash the hive with a soda solution followed by a water rinse.
One of the goals of beekeeping husbandry in protecting hives from wasp attack is to keep the level of wasp attack constrained to solitary scouting wasps by denying wasps access to the hives so that they never get to feed in the vicinity of the hives. This is where the design of hive entrances is so critical. A good hive entrance will be the difference between thriving success and calamity and the secret is in the numbers of ranks of defending honeybees that the entrance accommodates which can only really be achieved by having 'tunnel' entrances.
I trust this is missive enough for you. I better get back to work. Busy fighting medicines shortages in the UK at the moment which is taking every ounce of strength.
