Wood Ant Translocation

Wood Ant Trans­lo­ca­tion Good Prac­tice Guidance

Con­tents

Back­ground 3 Decid­ing on meth­od of trans­lo­ca­tion 12 Acknow­ledge­ments 29 Wood ant nests 4 Reas­on 1: trans­lo­ca­tion of nests under Ref­er­ences 30 The wood ant year 5 dir­ect threat of destruc­tion Con­ser­va­tion status of wood ants 6 Ger­man meth­od 13 Appendix I 31 Whole nest excav­a­tion meth­od 16 The shin­ing guest ant (formi­coxenus nitid­u­lus) 7 Reas­ons 2: trans­lo­ca­tion to increase Over­view UK dis­tri­bu­tion, hab­it­at pref­er­ences and colony struc­ture of each spe­cies Myrme­co­philes 7 resi­li­ence or for eco­lo­gic­al res­tor­a­tion Par­tial nest trans­lo­ca­tion 18 Appendix 2 32 Per­mis­sions 8 Release of mated queens 20 What to con­sider when record­ing hab­it­at fea­tures at donor and recept­or sites Health and safety 8 Trans­lo­ca­tion of nar­row-headed ant nests 22 Appendix 3 34 Trans­lo­ca­tion prin­ciples 9 Whole nest trans­lo­ca­tion meth­od for Pros and cons of dif­fer­ent trans­lo­ca­tion meth­ods Reas­ons for trans­lo­ca­tion of wood ants 9 nar­row-headed ants 25 Appendix 4 36 Record­ing the trans­lo­ca­tion 28 Stages of trans­lo­ca­tion 10 Decision tree to help select meth­od of trans­lo­ca­tion Site hab­it­at assess­ment || Post-trans­lo­ca­tion mon­it­or­ing 28 Appendix 5 37 Using felt tiles 28 Trans­lo­ca­tion record­ing form tem­plate Mon­it­or­ing sched­ule 28 Signs of suc­cess 29 Appendix 6 38 Sep­ar­at­ing the dif­fer­ent spe­cies of wood ants

Back­ground

The aim of this guid­ance is to encour­age a more struc­tured approach to the trans­lo­ca­tion of wood ant nests and ensure that trans­lo­ca­tions are based on the most up to date meth­ods. Trans­lo­ca­tion of wood ant nests is a very spe­cial­ised area of con­ser­va­tion and it is hoped that this guid­ance can provide use­ful tools for non-spe­cial­ists (land man­agers, con­sult­ants, developers etc.) that may need to carry out this type of work.

Our know­ledge of wood ant beha­viour and eco­logy is increas­ing all the time, as is our under­stand­ing of the effects of trans­lo­ca­tion on colon­ies and their abil­ity to tol­er­ate dis­turb­ance. As such this is seen as a work­ing doc­u­ment that will likely be updated over time as new inform­a­tion becomes available.

There are doc­u­mented examples of wood ant trans­lo­ca­tion pro­jects that have been con­duc­ted in the UK and fur­ther afield. Exper­i­ences gained through these pro­jects have helped to shape this guidance.

This guid­ance will cov­er the fol­low­ing mound build­ing spe­cies of ants: South­ern Red Wood Ant (Formica rufa), Scot­tish Wood Ant (Formica aqui­lo­nia) and Hairy Wood Ant (Formica lugubris). These spe­cies have dif­fer­ent hab­it­at require­ments and dif­fer­ent colony struc­tures (see Appendix 1). For the rest of this report these spe­cies will be termed ​“wood ants”.

This guid­ance also includes Nar­row-headed Ant (Formica exsecta) which is also a mound build­ing ant and related to the wood ants, but dif­fers in bio­logy and eco­logy. These dif­fer­ences mean that a dif­fer­ent approach to trans­lo­ca­tion is required for this spe­cies, as such it is dis­cussed sep­ar­ately to the wood ants on page 22.

“Our know­ledge of wood ant beha­viour and eco­logy is increas­ing all the time, as is our under­stand­ing of the effects of trans­lo­ca­tion on colon­ies and their abil­ity to tol­er­ate disturbance.”

Wood ant nests

The nests of these spe­cies are highly com­plex struc­tures and are built over years, some­times decades.

The thatched mound on the sur­face is only a com­pon­ent of the whole nest and a sig­ni­fic­ant pro­por­tion of nest struc­ture also exists under­ground. A single colony of wood ants can con­sist of mul­tiple, inter­con­nec­ted nests with estab­lished for­aging trails exist­ing between them and the sur­round­ing habitat.

Although some nest mounds con­tain a single queen (known as mono­gyny), there can be mul­tiple queens with­in a single wood ant nest mound (poly­gyny). It is essen­tial to estab­lish wheth­er a nest mound belongs to a pop­u­la­tion known to be gen­er­ally mono­gyn­ous or poly­gyn­ous (see Appendix 1) and cap­tur­ing the queens is crit­ic­al for the abil­ity of the nest to sur­vive – par­tic­u­larly the case in mono­gyn­ous nests. If the queen is lost or killed the nest will become extinct. Poly­gyn­ous colon­ies have the abil­ity to be single nest (monodomy), or multi-nest colon­ies (poly­domy). Poly­do­m­ous nests res­ult from mated queens return­ing to their nat­al nest. One of these queens can then cre­ate a ​“bud” or ​“satel­lite” nest nearby which remains con­nec­ted to the nat­al nest. There­fore a single related colony can con­sist of sev­er­al inter­con­nec­ted nests. A wood­land may con­tain a large num­ber of nests, how­ever if all these nests are related inter­con­nec­ted nests then the actu­al pop­u­la­tion size will be low (owing to the ants being genet­ic­ally related to one another).

To reduce com­pet­i­tion for resources, wood ants defend their nests and ter­rit­or­ies aggress­ively from oth­er wood ants and also oth­er ant spe­cies. Wood ant colon­ies that are unre­lated to each oth­er will fight aggress­ively when they encounter each oth­er although sep­ar­ate colon­ies can co-exist in the same area of wood­land by main­tain­ing their own ter­rit­or­ies. The size and qual­ity of hab­it­at will determ­ine how many colon­ies can co-exist, and how big (sizes of indi­vidu­al nests and num­bers of nests) these colon­ies can be.

Ants are pred­at­ory insects, for­aging on a wide range of inver­teb­rates at all levels of the wood­land, from the ground to the tree can­opy. Inver­teb­rate prey is pre­dom­in­antly fed to the devel­op­ing brood (lar­vae).

The diet of the work­ers mostly com­prises hon­ey­dew from aph­ids in the tree can­opy. Nests will have estab­lished for­aging routes into the wood­land around them. Trees both young and mature are a vital source of aph­ids. The wood ant work­ers will often vis­it par­tic­u­lar trees to feed, and not neces­sar­ily those closest to the nest.

A South­ern Wood Ant (Formica rufa) work­er guard­ing a col­lec­tion of aphids.

The wood ant year

It is use­ful to under­stand how the activ­ity of ants changes through­out the sea­son as this often dic­tates how and when nests can be moved. Oppos­ite is a gen­er­al­isa­tion and tim­ing of events will vary depend­ing on factors such as spe­cies, loc­a­tion with­in the UK, nest alti­tude, loc­al cli­mate etc.

More detailed inform­a­tion on wood ants and their eco­logy can be found in the resources below:

• Cairngorms Nation­al Park Author­ity (2021) Guide to Wood Ants of the UK and related species
• Robin­son, E.J.H. & Stockan, J.A. (Eds) (2016) Wood Ant Eco­logy & Con­ser­va­tion. Cam­bridge Uni­ver­sity Press.
• Robin­son, E.J.H. & Stockan, J.A. (2021) Wood Ants (Formica rufa Spe­cies Group) in Encyc­lo­pe­dia of Social Insects. Chris­toph­er K. Starr (Ed). Spring­er, Germany.
• www​.wood​ants​.org​.uk
• www​.antwiki​.org/wiki

Cal­en­dar of Wood Ants

Tim­ing	Event
Novem­ber-March	Hiberna­tion
March-April	Spring swarm­ing. Tim­ing of emer­gence is dependent
on ambi­ent tem­per­at­ure and levels of sun­shine. In south­ern UK wood
ants can emerge as early as Feb­ru­ary, depend­ing on weather.
	Activ­ity of the work­ers begins when the intern­al nest tem­per­at­ure rises to
between 25 – 30°C.
	Work­ers will then cluster on the sur­face of the nest in a dense mass
to absorb heat from the sun (see Fig­urel below right).
May-Octo­ber	This is the main sea­son for wood ant work­er activ­it­ies. This includes
for­aging, aph­id farm­ing, repair­ing and build­ing nest. The num­ber of active
work­ers involved in for­aging peaks in mid-summer.
June-Septem­ber	Rais­ing work­er offspring
May-June	Rais­ing sexu­al off­spring (from eggs laid in late winter/​early spring).
May-June	Emer­gence of males and vir­gin queens, mat­ing flights. This is usu­ally confined
to a rel­at­ively short win­dow of time. In south­ern Eng­land can be as early as
May, in north­ern Scot­land may be as late as July/​early August.

Cal­en­dar of Nar­row-headed Ant

Tim­ing	Event
Novem­ber-March	Hiberna­tion
March-April	Work­ers become act­ive again (but do not show swarming/​clustering behaviour
as seen in wood ants). Spring emer­gence in Scot­land is likely to be later than
south­ern England.
May-Octo­ber	Gen­er­al work­er activ­ity and for­aging, aph­id farm­ing, repair­ing and building
nest. Num­ber of act­ive work­ers involved in for­aging peaks in mid-summer.
May-June	Rais­ing sexu­al off­spring (from eggs laid in late winter/​early spring).
June-Septem­ber	Rais­ing work­er offspring
July-August:	Emer­gence of males and vir­gin queens, mat­ing flights. This is usu­ally con­fined to
a rel­at­ively short win­dow of time.

Fig­ure I

Con­ser­va­tion Status of wood ants

Wood ants are not leg­ally pro­tec­ted. How­ever some of the spe­cies are of con­ser­va­tion con­cern and lis­ted as pri­or­ity spe­cies for con­ser­va­tion. All pub­lic bod­ies have a biod­iversity duty to pro­tect and con­serve all wild­life, not just spe­cif­ic pro­tec­ted sites or pro­tec­ted species.

It is con­sidered good eco­lo­gic­al prac­tice to avoid delib­er­ately harm­ing wood ants and their nests, par­tic­u­larly in light of their import­ant roles with­in wood­land ecosystems.

• Envir­on­ment Act 2021, Nat­ur­al Envir­on­ment & Rur­al Com­munit­ies Act (2006) Sec­tion 40 and Sec­tion 42 (Eng­land and Wales respect­ively), Nature Con­ser­va­tion (Scot­land) Act 2004 (Scot­land), Wild­life and Nat­ur­al Envir­on­ment Act (North­ern Ire­land) 2011 (North­ern Ireland)

Over­view of the con­ser­va­tion status of each species:

Spe­cies	Status
South­ern Red Wood Ant (Formica rufa)	IUCN status: ​“Near Threatened” (last assessed 1996) Sub­ject to an action plan in the War­wick­shire, Cov­entry and Soli­hull Loc­al Biod­iversity Action Plan and the Har­row (Lon­don Bor­ough) Biod­iversity Action Plan.
Scot­tish Wood Ant (Formica aquilonia)	IUCN status: ​“Near Threatened” (last assessed 1996) North­ern Ire­land Pri­or­ity Spe­cies (Wild­life and Nat­ur­al Envir­on­ment Act (North­ern Ire­land) 2011) Sub­ject to an action plan in the Cairngorms Nation­al Park
Hairy Wood Ant (Formica lugubris)	IUCN status: ​“Near Threatened” (last assessed 1996) Sub­ject to an action plan in the Cairngorms Nation­al Park
Nar­row-Headed Ant (Formica exsecta)	Classed as Endangered in the UK accord­ing to the GB Red List. Nat­ur­al Envir­on­ment & Rur­al Com­munit­ies Act (2006) Sec­tion 41 – lis­ted under ​“Spe­cies of Prin­cip­al Import­ance” Nature Con­ser­va­tion (Scot­land) Act 2004 – lis­ted as a pri­or­ity spe­cies on the Scot­tish Biod­iversity List under the cat­egor­ies ​“Con­ser­va­tion Action Needed” and ​“Avoid Neg­at­ive Impacts”. Sub­ject to an action plan in the Cairngorms Nation­al Park (2019−2024) and is lis­ted on the ​“Devon Spe­cial Spe­cies” by the Devon Loc­al Nature Partnership.

The Shin­ing Guest Ant (Formi­coxenus nitidulus)

The Shin­ing Guest Ant is an ant spe­cies that lives inside wood ant mounds. It cre­ates its own nest inside the wood ant mound and for­ages with­in the nest, pro­tec­ted by a cuticle coat­ing that the wood ants find repel­lent. It is not found with­in every single wood ant nest and due to its tiny size and secret­ive life­style, very little is known about this spe­cies. It is lis­ted as a pri­or­ity spe­cies for con­ser­va­tion in Eng­land and Scot­land (see below). Its status as a pri­or­ity spe­cies accords pri­or­ity status to wood ants, as it is depend­ent upon South­ern Red Wood Ant, Scot­tish Wood Ant and Hairy Wood Ant in the UK for its existence.

Over­view of status:

• Nat­ur­al Envir­on­ment & Rur­al Com­munit­ies Act (2006) Sec­tion 41 (Eng­land – ​“Spe­cies of Prin­cip­al Importance”)
• Nature Con­ser­va­tion (Scot­land) Act 2004 lis­ted as a pri­or­ity spe­cies on the Scot­tish Biod­iversity List under the cat­egory ​“Watch­ing Brief Only”.
• IUCN status: ​“Vul­ner­able” (last assessed 1996)
• Sub­ject to an action plan in the Cairngorms Nation­al Park

Myrme­co­philes

In addi­tion to the ants them­selves, wood ant nests often play host to oth­er inver­teb­rate spe­cies which depend upon the con­di­tions with­in the nest for all or part of their life­cycle (known as myrme­co­philes*), mak­ing the nests small eco­sys­tems in their own right.

• For more inform­a­tion on myrme­co­philes in wood ant nests, see Robin­son, N.A. & Robin­son, E. J. H. (2013) and Chapter 8 of Robin­son, E.J.H. & Stockan, J.A. (Eds) (2016)

Per­mis­sions

Where trans­lo­ca­tions are neces­sary, these should be under­taken fol­low­ing the Inter­na­tion­al Uni­on for the Con­ser­va­tion of Nature (IUCN) Guidelines for Rein­tro­duc­tions and Oth­er Con­ser­va­tion Trans­lo­ca­tions. Trans­lo­ca­tion of wood ant nests will require the per­mis­sion of the landown­er at the donor and recip­i­ent sites.

Where the site is des­ig­nated, addi­tion­al con­sents will be required from the rel­ev­ant gov­ern­ment con­ser­va­tion body: Nat­ur­al Eng­land, Nature Scot, Nat­ur­al Resources Wales, Coun­cil for Nature Con­ser­va­tion & the Coun­tryside (North­ern Ireland).

In Scot­land the IUCN guidelines have been developed into a code on how to assess and plan con­ser­va­tion trans­lo­ca­tions in Scot­land: Scot­tish Code for Spe­cies Trans­lo­ca­tions. The code con­tains forms that must be com­pleted and sub­mit­ted to Nature Scot for a licence this must be car­ried out for all spe­cies trans­lo­ca­tions in Scot­land. The form allows you to record the trans­lo­ca­tion pro­cess and steps to reduce risk of neg­at­ive outcomes.

In Eng­land, DEFRA have pub­lished Rein­tro­duc­tions and oth­er con­ser­va­tion trans­lo­ca­tions: code and guid­ance for Eng­land (May 2021). This code is based on the IUCN guidelines and is designed to align with the Scot­tish Code to encour­age con­sist­ency across the UK.

Health and Safety

Trans­lo­cat­ing wood ant nests, nest mater­i­al and ants is stress­ful for the ants and they will defend them­selves by spray­ing form­ic acid and bit­ing. When mov­ing large amounts of nest mater­i­al, the volume of form­ic acid can be sig­ni­fic­ant and can irrit­ate the skin, eyes and res­pir­at­ory system.

It is there­fore strongly recom­men­ded that for any wood ant trans­lo­ca­tion work and hand­ling of ants and nest mater­i­al, the fol­low­ing Per­son­al Pro­tect­ive Equip­ment is used:

• Safety goggles

• A valved face mask to cov­er the nose and mouth

• Gloves (tough garden­ing gloves recom­men­ded for shov­el­ling and mov­ing nest material)

• Sturdy foot­wear, full length trousers and a top that cov­ers the arms. Trousers should be tucked into long socks or gaiters should be worn.

Trans­lo­ca­tion Principles

Trans­lo­ca­tion of wood ant nests must always be the last resort. The eco­lo­gic­al mit­ig­a­tion hier­archy should be fol­lowed (CIEEM 2018), seek­ing to avoid any impact on wood ant nests as the pri­or­ity. If this is not pos­sible, mit­ig­a­tion should be designed to lim­it impacts on the nest while remain­ing in situ. Only where avoid­ance and in situ mit­ig­a­tion are not pos­sible should trans­lo­ca­tion be con­sidered. The aim should always be to design devel­op­ment, forest plans etc. that com­ple­ment the nat­ur­al eco­logy of wood ants and avoid the need to dis­turb them.

Reas­ons for trans­lo­ca­tion of wood ants

Reas­on 1:

To pre­vent loss of wood ant colon­ies due to a dir­ect threat of extinc­tion (e.g. devel­op­ment, tree remov­al, irre­vers­ible hab­it­at change): this must be a last resort only, as it is best prac­tice to leave wood ant nests in their ori­gin­al loc­a­tion and with suf­fi­cient hab­it­at to allow colon­ies to survive.

Reas­on 2:

To rein­tro­duce wood ants to his­tor­ic­al areas to pro­mote eco­lo­gic­al res­tor­a­tion and eco­lo­gic­al resi­li­ence, cap­it­al­ising on the role wood ants play as key­stone spe­cies and eco­sys­tem engineers.

For reas­on 2 there must be clear jus­ti­fic­a­tion for re-loc­at­ing wood ant nests and trans­lo­ca­tion should only be under­taken if wood ants can­not dis­perse to these areas on their own, there is his­tor­ic­al evid­ence to sug­gest that wood ants were present in the past, or that the recip­i­ent site is with­in their nat­ive range. There must be clear bene­fits to mov­ing wood ants, both for the wood ant colony and also the eco­logy of the recip­i­ent site. There should be no sens­it­ive spe­cies which could be adversely affected (includ­ing exist­ing wood ant colon­ies) and no factors which would affect long term sur­viv­al of the wood ant colon­ies at the new loc­a­tion (i.e. future changes in management).

All meth­ods of trans­lo­ca­tion need to con­sider the fol­low­ing prin­ciples (adap­ted from Hughes, 2008):

a. Wood ant nests should always be moved in a way that retains at least the nest lay­ers (even if using the Ger­man meth­od see page 13).

b. Recip­i­ent sites must be chosen and pre­pared in advance of the wood ants being moved, with neces­sary sur­vey work being com­pleted before the trans­lo­ca­tion (see Appendix 2).

C. Wood ant nests should only be moved dur­ing peri­ods of low activ­ity in early spring*. The ambi­ent air tem­per­at­ure should be between 5 and 10°C. Tim­ing must coin­cide with 2 – 3 days fair weath­er post-trans­lo­ca­tion so that the ants have good con­di­tions to rebuild the nest.

d. Wood ants (and Nar­row-headed Ant) should nev­er be moved dur­ing the winter hiberna­tion peri­od – at this time the ants are deep inside the nest in the under­ground com­pon­ent where the tem­per­at­ures are more stable and they can avoid frost. They enter a peri­od of very low activ­ity, util­ising fat stores to sur­vive. Excav­a­tion of the nest at this time would expose the wood ants to low tem­per­at­ures which could kill them. Using up their winter stores at this time when they can­not be replen­ished would cause the over­win­ter­ing work­ers and queens to starve.

e. Trans­lo­ca­tion must con­sider the dis­tances that nests can be real­ist­ic­ally moved, the ter­rain and wheth­er nests will be moved by hand or in a vehicle. Dis­tances trav­elled and the time nests are being moved should be kept to an abso­lute min­im­um to avoid too much stress on the ants.

f. Trans­lo­cated nests must be mon­itored and integ­rated into long-term man­age­ment plans to ensure their sur­viv­al and abil­ity to thrive.

• Key excep­tion to this is trans­lo­ca­tion of Nar­row-headed Ant nests see page 18 and the par­tial nest method

Stages of translocation

When plan­ning a trans­lo­ca­tion or rein­tro­duc­tion, a meth­od state­ment should be com­piled, cov­er­ing all key aspects of the trans­lo­ca­tion. This should include:

• Reas­on for translocation/​introduction,
• Choice of recept­or site(s) based on detailed hab­it­at assessment:
• Hab­it­at suit­ab­il­ity study in the sea­son pri­or to trans­lo­ca­tion. Recept­or sites should aim to be as close to the donor site in hab­it­at struc­ture as possible,
• Identi­fy­ing pre­cise pin­point loc­a­tions for trans­lo­cated nest(s) at the recip­i­ent site(s).
• Descrip­tion of how the nest trans­lo­ca­tion will be under­taken prac­tic­ally (pre­par­a­tion at the recip­i­ent site; tim­ing; equip­ment used; nest extrac­tion, trans­port and install­a­tion methods)
• Safe­guards to min­im­ise dis­turb­ance to oth­er wild­life dur­ing the trans­lo­ca­tion operation,
• Con­sid­er­a­tion of impacts, and repair­ing any dam­age from the trans­lo­ca­tion oper­a­tion, at the donor site.
• Post-trans­lo­ca­tion after­care (pro­gramme of sup­ple­ment­ary feeding),
• Post-trans­lo­ca­tion mon­it­or­ing (at recip­i­ent and donor sites),
• Oth­er rel­ev­ant inform­a­tion: maps, track­ing routes across site(s) for any vehicle movements,
• Health and Safety risk assessment.

Site hab­it­at assessment

• 1) Assess­ment of donor sites
• Plot the loc­a­tion of all nests requir­ing trans­lo­ca­tion and clearly mark them if necessary
• Identi­fy ant spe­cies – each spe­cies has dif­fer­ent hab­it­at pref­er­ences (Appendix 1) so it is import­ant to know which spe­cies is present. An eco­lo­gist with exper­i­ence of work­ing with ants should be con­sul­ted for advice
• Sur­vey and record hab­it­at with­in 10m and 25m buf­fer area around each nest requir­ing trans­lo­ca­tion (Cath­rine 2015a). This will allow the hab­it­at imme­di­ately around the nest to be assessed, and also the wider hab­it­at which the wood ants are likely to be for­aging in. This detailed assess­ment is import­ant to ensure a recept­or site is chosen that matches the hab­it­at of the donor site as closely as pos­sible. A tem­plate for record­ing this sur­vey inform­a­tion is avail­able in Appendix 2.

If nests or nest material/​ants are being trans­lo­cated to intro­duce wood ants for reas­on 2 on page 18, addi­tion­al factors will need to be considered:

• There must be clear jus­ti­fic­a­tion for intro­du­cing wood ants into hab­it­at where they are cur­rently absent.
• The donor pop­u­la­tion should be healthy, and remov­al of indi­vidu­als or nest mater­i­al should not have a sig­ni­fic­ant neg­at­ive effect on the colony’s sur­viv­al. The excep­tion to this would be where the donor pop­u­la­tion is at high risk of extinc­tion at its cur­rent loc­a­tion and the only option is to move the donor pop­u­la­tion to a site which would increase their chance of survival.
• Rein­tro­duc­tion of wood ants to a new area will require care­ful con­sid­er­a­tion of the qual­ity of hab­it­at at the recip­i­ent site and eco­lo­gic­al implic­a­tions of rein­tro­du­cing wood ants to that hab­it­at, includ­ing poten­tial impacts on oth­er species.

2) Assess­ment of recept­or sites

The hab­it­at of the recept­or site should match the donor site as far as pos­sible. It is highly recom­men­ded that the recept­or site is assessed at dif­fer­ent times of year to estab­lish effects of drain­age and shad­ing. As well as meet­ing the broad­er hab­it­at require­ments of the wider area, the imme­di­ate vicin­ity of the recept­or loc­a­tion should be as sim­il­ar as pos­sible to the donor site. These should aim to be in sunny, sheltered pos­i­tions where the ground flora and sur­round­ing trees and shrubs will not shade the nest. Suit­able hab­it­at at the recept­or site should extend to 20m away from the chosen nest micros­ite, in order to allow the ants to relo­cate and bud.

It must be noted that the dis­tance between the donor and recept­or sites is also an import­ant con­sid­er­a­tion and will be an import­ant factor in determ­in­ing the meth­od of trans­lo­ca­tion chosen. There are cases of wood ants being trans­por­ted over huge dis­tances suc­cess­fully, such as the intro­duc­tion of Hairy Wood Ant nests from Italy to Canada in the 1970s (Fin­neg­an 1975). How­ever, trans­port­a­tion dis­tances should be kept to a min­im­um and the time ants are cap­tive kept as short as pos­sible to avoid too much stress on the ants and risk of suf­foc­a­tion and crush­ing caused by the weight of nest material.

A check­list of factors to note and record at recept­or sites is giv­en in Appendix 2.

Decid­ing on meth­od of translocation

Reas­on 1:

Trans­lo­ca­tion of nests under dir­ect threat of destruction

Aim: To trans­lo­cate all nests and as much of the nest mater­i­al as pos­sible. It is impossible to col­lect all of the indi­vidu­al ants and inev­it­ably some will be left behind.

Object­ive: To retain the loc­al pop­u­la­tion and its genet­ics by estab­lish­ing viable nests in altern­at­ive loc­a­tions — this is done by cap­tur­ing queens with enough of a work­force to sup­port them.

Meth­ods: There are two meth­ods that are likely to be used, both of which aim to col­lect as much of the ori­gin­al nest mater­i­al as possible.

Meth­od I — GER­MAN METHOD

Meth­od 2 — WHOLE NEST EXCAV­A­TION METHOD

See Appendix 3 for the pros and cons of each of the cur­rent doc­u­mented trans­lo­ca­tion meth­ods for ants. A flow chart is provided in Appendix 4 to assist in decid­ing between trans­lo­ca­tion methods.

Prin­ciples com­mon to both methods:

• Trans­lo­ca­tion should be car­ried out in the morn­ing when it is cool­er and ants are less likely to be highly act­ive and for­aging away from the nest
• Choice of recept­or site for the nest must be made pri­or to trans­lo­ca­tion recept­or sites for trans­lo­cated nests should be care­fully selec­ted to be as sim­il­ar to the donor site as pos­sible and must be of sunny, sheltered loc­a­tions that are south or south-east facing. In advance of the trans­lo­ca­tion, the indi­vidu­al recept­or sites will require some pre­par­a­tion to accept the nest mater­i­al and access­ible bare soil for the ants to tun­nel into. Recept­or site pre­par­a­tion involves scrap­ing an area of the ground sur­face to remove sur­face veget­a­tion, approx­im­ate to the size of the nest being moved. The dia­met­er and depth of the depres­sion should reflect the dimen­sions of the nest being moved. The excav­ated mater­i­al can be moun­ded up on the north­ern side of the depres­sion and may help to provide addi­tion­al struc­ture and warmth for the nest (Jukes & Price 2016). Some trans­lo­ca­tion meth­ods where nest struc­ture isn’t retained involve pla­cing tree brash and branches in the cre­ated hol­low to provide ​“scaf­fold­ing” for the ants to build around (Jukes & Price 2016, Attewell 2020, Attewell 2021).
• When mov­ing mul­tiple nests, suf­fi­cient space should be giv­en to each nest there should only be one nest every 100m where nests are unre­lated. This will give indi­vidu­al nests room to relo­cate and expand and pre­vents con­flict between nests, if nests are not related to each oth­er. Where nests are known to be related to one anoth­er (i.e. form part of a poly­do­m­ous colony) then dis­tance between nests can be much smal­ler, e.g. 15 – 20m (Jukes & Price 2016).
• Sup­ple­ment­ary feed­ing post trans­lo­ca­tion is required to provide an imme­di­ate energy source to the ants until they can estab­lish new for­aging routes. Sup­ple­ment­ary feed can take the form of chopped fruit (apple/​pear), a home-made mash (made of bread, honey, raw egg and water), hon­ey­bee fond­ant, or pur­pose made ant gels*.

* An example of ant gel can be found here

GER­MAN METHOD

This meth­od is based on a trans­la­tion of a meth­od by the Deutsche Amei­s­ens­chutzwarte (Ger­man Office for the Pro­tec­tion of Ants). It involves scoop­ing up the nest mater­i­al into con­tain­ers (such as hes­si­an sacks or large plastic bar­rels) which are then emp­tied at the donor site.

Tim­ing:

• Aim to coin­cide with the swarm­ing beha­viour of the ants in early spring, when they start to become act­ive after hiberna­tion. At this time the ants will be high­er up with­in the mound; on top of it or in the top­most lay­er of soil around the mound. Obser­va­tion­al vis­its to the nests in advance of the trans­lo­ca­tion will help to determ­ine the activ­ity level of the ants. It is import­ant that queens are cap­tured dur­ing the trans­lo­ca­tion and at this time of the year queens are usu­ally above ground inside the mound and easi­er to locate.
• Avoid sum­mer months when work­ers are act­ive and dis­persed away from the nest this risks los­ing sig­ni­fic­ant num­bers of work­ers. Trans­lo­ca­tions should only be under­taken at this time of year as a last resort.
• Avoid late sum­mer and autumn as this is when the colony activ­ity starts to slow down and if moved dur­ing this peri­od ants may not have enough time to repair the nest and restore for­aging routes before winter. Trans­lo­ca­tions should only be under­taken at this time of year as a last resort.
• Should avoid the hiberna­tion peri­od (Novem­ber-March) at all costs
• Should be car­ried out in the morn­ing and com­pleted by mid­day this way the ants will be cold and slow and mostly situ­ated with­in the mound. Choose a day with good settled weath­er (no frost, warm and dry, between 5 and 10°C). The day of trans­lo­ca­tion should be fol­lowed by 2 – 3 days of settled weath­er so that the ants can repair the nest and devel­op for­aging routes.

GER­MAN METH­OD – continued

Equip­ment:

• Min­im­um of 3 people, more depend­ing on size of nest(s).
• Wide, flat, coal-type shovels (poten­tially less dam­aging than sharp dig­ging spades) for the thatch, and con­ven­tion­al spades for the sub­ter­ranean parts of the nest.
• Breath­able con­tain­ers for car­ry­ing the ants that pro­tect them from dir­ect sun­light and absorb the form­ic acid they spray in defence. Old-style hes­si­an potato sacks made from nat­ur­al fibres work well. A recom­men­ded size is 90cm x 60cm (lar­ger sacks may be too heavy to lift when full) (Jukes & Price 2016). Large plastic bar­rels have also been used suc­cess­fully and reduces the num­ber of work­ers lost or escap­ing dur­ing trans­port (Phil Attewell, pers. comm, and also Ger­man Office for Pro­tec­tion of Ants).
• A pen to write the nest num­ber on to the per­tain­ing sack or barrel.
• String or oth­er cord to tie up the sacks (or if using large plastic bar­rels, FluonTM paint painted below the top of the con­tain­er can be used to pre­vent ants from escaping).
• A means of trans­port­ing the con­tain­ers with nest mater­i­al from donor site to recept­or site (wheel­bar­row, pick-up truck etc. depend­ing on dis­tances involved and terrain).

GER­MAN METH­OD – continued

Pro­ced­ure:

1. Pre­pare the recept­or site.
2. Work­ing in pairs, one per­son hold­ing open the con­tain­er, one per­son shov­el­ling the nest, shovel up as much of the massed ants and nest mater­i­al as pos­sible, in as few scoops as pos­sible to reduce time taken and stress caused to the ants. Depend­ing on the size of the nest, this will likely require sev­er­al sacks or bar­rels. Fill con­tain­ers only half full to avoid crush­ing at the bot­tom, adding small branches and twigs whilst the bag is being filled with nest mater­i­al to help alle­vi­ate pres­sure from the weight of mater­i­al. Tie up each con­tain­er as quickly as pos­sible after filling.
3. Saws may be required where there are roots embed­ded in the nest structure.
4. Excav­ate the nest as far as the soil struc­ture will allow, until there are no more signs of ant tun­nels. Take care to look for queens (see Appendix 6) (it’s worth hav­ing an assist­ant who is not shov­el­ling that can focus on doing this) which must be care­fully col­lec­ted by hand or with a small con­tain­er or into pots for release at the recept­or site.
5. Label the con­tain­ers in the order that they are excav­ated so that they can be emp­tied at the recept­or site in the cor­rect order (deep­est lay­ers first, work­ing up towards the top­most thatch).
6. Trans­port the con­tain­ers to the recept­or site – the trans­port route should be planned in advance so that it can be kept as short as pos­sible and avoid bumpy ter­rain. Depend­ing on the dis­tance between donor site and recept­or site this could be done in a wheel­bar­row for example or in the back of a pick-up truck, but whichever is chosen the speed of trans­port should be slow and care­ful to avoid too much rough hand­ling of the con­tain­ers. If using sacks, these should be loaded flat on their sides to reduce com­pres­sion pres­sure on the ants. Aim to keep the time that the ants are held in the trans­port­a­tion sacks as short as possible.
7. At the recept­or sites, open the con­tain­ers and care­fully tip the mater­i­al over the pre­pared hol­low, in the cor­rect order to main­tain the lay­ers of mater­i­al. If using hes­si­an sacks, each sack should be cut into two or three pieces and placed with the nest mater­i­al – this will ensure any ants and small inver­teb­rates that live inside the nest are retained. The hes­si­an sack will con­trib­ute to the nest frame­work and will even­tu­ally rot away.
8. The ants should be provided with sup­ple­ment­ary food imme­di­ately after trans­lo­ca­tion – this sus­tains the work­ers while they estab­lish new for­aging routes. Record and pho­to­graph the new loc­a­tion of the nest. It is likely that the ants will re-assemble the nest in a slightly dif­fer­ent pos­i­tion, a short dis­tance away, or split into mul­tiple mounds (if the ori­gin­al nest was polygynous).
9. If the nest is to be situ­ated with­in prox­im­ity of con­struc­tion work, the nest should be marked and pro­tect­ive fen­cing or a bar­ri­er erec­ted to pre­vent nest being damaged.

Fol­low-up care:

1. Check the ori­gin­al donor site for three days after the trans­lo­ca­tion for any remain­ing ants col­lect these and move them to the new loc­a­tion. Check after three months for any signs of re-estab­lish­ment at the donor site*.
2. Con­tin­ue to replen­ish and provide sup­ple­ment­ary food every few days for at least two weeks.
3. Remove any pro­tect­ive fen­cing, if present, once this is no longer needed.

• If a queen and enough work­ers are left behind at the ori­gin­al donor site, a nest may re-estab­lish at the ori­gin­al site. This is why it is import­ant to excav­ate as much nest mater­i­al and as many ants as pos­sible dur­ing the trans­lo­ca­tion. It is import­ant to check the donor sites after the trans­lo­ca­tion work — ants left behind may re-estab­lish a nest or wood ants from nearby may also col­on­ise the area. There may be a need to carry out a second trans­lo­ca­tion if there is a suf­fi­cient time delay for wood ants to estab­lish a new nest between the first trans­lo­ca­tion and site clear­ance and this should be factored into pro­ject plans.

WHOLE NEST EXCAV­A­TION METHOD

Instead of col­lect­ing into sacks, the prin­ciple is to col­lect the nest as a whole, as far as is pos­sible and move it as a single mass, retain­ing struc­ture. If an excav­at­or is already on site, this may be a cost and time effi­cient approach.

Tim­ing: As Ger­man method.

Equip­ment: An excav­at­or with a dig­ging buck­et exceed­ing the size of the nest being moved should be used so that it can excav­ate the nest in a single scoop. Some hand excav­a­tion may still be required along­side a mech­an­ic­al excavation.

Pro­ced­ure:

1. Pre­pare the recept­or site.
2. Clear the route between the nest and the recept­or site so there are no haz­ards or obstacles (which could increase vibra­tion and dam­age nest architecture).
3. If the nest is con­struc­ted around a fea­ture, such as a dead tree or stump, it may be neces­sary to under­take some pre­par­at­ory hand dig­ging and saw­ing of roots before using an excavator.
4. Excav­ate using excav­at­or with a dig­ging buck­et attach­ment exceed­ing the size of the nest being moved. Aim to excav­ate the entire nest and any fea­ture it may be built around in a single scoop.
5. Move nest as slowly and stead­ily as pos­sible (around 2.5 mph if using an excavator).
6. Some hand excav­a­tion (as Ger­man meth­od) and col­lec­tion of nest mater­i­al and ants into con­tain­ers may be required, if the excav­a­tion with the dig­ger does not man­age to cap­ture the entire nest.
7. Depos­it nest in recept­or site hol­low gently, at same ori­ent­a­tion as at donor site.
8. Provide sup­ple­ment­ary food (see Ger­man method).
9. Mark the nest and provide pro­tect­ive fen­cing as required.

WHOLE NEST EXCAV­A­TION METH­OD – continued

Fol­low-up care:

1. Check the ori­gin­al donor site for three days after the trans­lo­ca­tion for any remain­ing ants col­lect these and move them to the new loc­a­tion. Check after three months for any signs of re-estab­lish­ment at the donor site (see foot­note on page 15).
2. Con­tin­ue to replen­ish and provide sup­ple­ment­ary food every few days for at least two weeks.
3. Remove any pro­tect­ive fen­cing, if present, once this is no longer needed.

It is not uncom­mon when using the above meth­ods for wood ants to re-loc­ate their nests shortly after trans­lo­ca­tion. The ants may find a more suit­able loc­a­tion for the nest a short dis­tance away and re-build it there, or the nest may re-form as two mounds rather than one. Nest mounds may relo­cate sev­er­al times fol­low­ing trans­lo­ca­tion before the even­tu­ally ​“settle” (Andy Jukes, Pers. Comm.) there­fore it is import­ant that there is suit­able hab­it­at with­in 20m of the chosen micro-site to give the ants space to move about and relo­cate if they need to.

Tree spade

There is no record of a tree spade being used to trans­lo­cate wood ant nests or nests of Nar­row-headed Ant, though there has been suc­cess in using this meth­od to relo­cate nests of Yel­low-Mead­ow Ants (Lasi­us flavus) (King & Balfour 2019) which is a sub­ter­ranean spe­cies and cre­ates hills of excav­ated soil. There is poten­tial that this could be used to trans­lo­cate wood ant nests under the right con­di­tions; large machinery is obvi­ously required so access needs to be con­sidered. If this type of machinery is already on site for oth­er pur­poses it might present a cost-effect­ive option.

King & Balfour (2019) used a tree spade moun­ted on a com­pact load­er, with a scoop dia­met­er of 1.1 m and pro­duced a con­ic­al soil lump 0.85 cm deep. The trans­lo­cated ant-hills of Yel­low-Mead­ow Ants were up to 0.7 m in dia­met­er. The nests were trans­por­ted I km from the donor site to the recip­i­ent site and the com­pact load­er was able to travel at over 20 km/​hr which reduced the time taken dur­ing trans­lo­ca­tion. All five of the nests that were trans­lo­cated were still act­ive and intact 17 months after the translocation.

A vari­ety of spades, grabs and boxes can be moun­ted on com­pact load­ers offer­ing a vari­ety of scoop sizes and shapes. A four-wheel drive com­pact load­er provides man­oeuv­rab­il­ity whilst min­im­ising ground disturbance.

As with the above mech­an­ic­al excav­a­tion meth­od, some hand excav­a­tion and col­lec­tion of nest mater­i­al and ants into con­tain­ers is likely to be required, if the nest is very large and the excav­a­tion does not man­age to cap­ture the entire nest.

The pro­ced­ure with regards to tim­ing, pre­par­a­tion of recept­or site, sup­ple­ment­ary feed­ing etc. would still apply see Ger­man Meth­od and Whole Nest Methods.

Reas­ons 2:

Trans­lo­ca­tion to increase resi­li­ence or for eco­lo­gic­al restoration

Because this type of trans­lo­ca­tion has the aim of mov­ing nests in