La Mikaelson perdida (TW x TO)
Wallpaper
- Have you ever seen a 16 year old wolf before?
log in or sign up
Animated gif about gif in Emliee ๐ by Kianna on We Heart It
- Collector Plates
LEO
- Wolf life
๐ธ
โ ๐๐๐ซ๐จฬ๐ง๐ข๐๐ ๐๐จ๐๐ ๐โ
- B o o k s & q u o t e s.
๐๐๐๐๐๐๐๐ ๐ฟ๐๐๐๐ ๐๐๐๐
- Home Dreams
Register - Login
- Grey Wolves
Veronica Lodge ๐ฆ
- Animal Totems: White Wolf
m`
- Animal-Spirit-Totems
- Breaking News
- canis lupus
- cool picture of a melanistic maned wolf
- ๐ฅ Arctic Wolf
- Adorable animals
- Wolf Pup
- Animals - Wolves
- Animal
- Displaying trophies
- Animals
- Wolfs
- canis lupus
- Bloodlusted Grey Wolf with terrifying eyes feasts on deer carcass
- Animals
- Farm Logo
- Conch Salad...
- red wolves
- I keep getting wolf videos suggested to me on Facebook, and now theyre becoming one of my favorite animals. Simply majestic...
- skin and bones
- scroll saw
- aprรจs ski
- Animaux
- Alexa gscene water
- Wolf population
- Colorado โค๏ธ
- WILDLAND FIREFIGHTER
๐ฎ๐น Allโinterno di un branco tipo di lupi si ritrova una coppia dominante (detta alfa), un individuo o una coppia immediatamente successiva in importanza (detta beta), alcuni individui di medio rango fino ad arrivare ad uno o piuฬ lupi di rango inferiore (detti omega). Gli alfa comandano tutto il gruppo, i beta dirigono i lupi di medio livello e tutti gli adulti comandano gli individui di medio e basso rango. Mentre i due estremi della gerarchia tendono allโimmutabilitaฬ dei ruoli, eccetto i casi di ferimenti o morte, eฬ il medio rango ad essere piuฬ dinamico socialmente. Diversa considerazione spetta ai cuccioli, che fino allโetaฬ della maturitaฬ sessuale restano fuori da questi delicati equilibri, mentre le femmine sono sempre in seconda posizione rispetto al maschio pari grado ๐บ โข ๐ฌ๐ง Within a pack of wolves there is a dominant pair (called alpha), an individual or a pair immediately following in importance (called beta), some individuals of medium rank up to one or more wolves of lower rank ( called omega). The alpha command the whole group, the beta direct the mid-level wolves and all adults command the medium and low-ranking individuals. While the two ends of the hierarchy tend to the immutability of roles, except in cases of injury or death, it is the middle rank that is more socially dynamic. Different consideration is given to the puppies, who remain out of these delicate balances until the age of sexual maturity, while the females are always in second position compared to the male of the same degree ๐บ ๐พ ๐พ ๐พ ๐ฒ๐ฒ๐ฒ Wanna see your Wolf on my page? DM for collab ๐บ ๐ฒ๐ฒ๐ฒ ๐พ ๐พ ๐พ โข Go follow โข 1) @_amira_thewolfdog ๐บ 2) @shaka_kaya_czechwolfdogs ๐บ 3) @hippie_saarloos ๐บ 4) @kraken_the_wolfdog ๐บ 5) @greywind.wolfdog ๐บ 6) @nymeria.saarlooswolfdog ๐บ 7) @baltic_the_wolfdog ๐บ 8) @lo_scatto_rubato ๐บ 9) @ilupidellealpi ๐บ 10) @shanti.wolfdog ๐พ โข TAG โข #animals #animal #pet #dog #cat #dogs #cats #photooftheday #cute #pets #instagood #animales #๐บ #love #nature #animallovers #pets_of_instagram #petstagram #petsagram #wolf #wolves #wolfpack #wolfsoul #lonewolf๐บ #wolfhowl #greywolf #wolffootprint๐พ - @___w_o_l_v_e_s___ on Instagram
- ANimaiS
- Wolf Moon
- Alpha Wolf
- In my town of South Lake Tahoe there are two breakfast joints: Berts and Ernies, across the street from each other
- Beautiful wolves
- Artist Beverly Doolittle, Camouflage Artist
- Wolf Love
- Animals
- Wolf Sketch
- Cรฃes
- Howling wolf tattoo
- Cute Animals
- A Sweet Poem
- spirit animal wolf
- Agricultural InfoGraphs
- Bubbas wolves
- @wolfworldnet on Instagram
- Wolf Quotes
- Animals
- Wolfs
- Art: animals
- Anti-Fur Poster from PETA, date unknown
- Animal kingdom
- Animals
- Art ideas - prismacolor
- one board to rule them all
Photo of the day : wolf!!๐บ๐ . Double~ tap~๐ . @animal_pocket_๐ The wolf, also known as the grey/gray wolf or timber wolf, is a canine native to the wilderness and remote areas of Eurasia and North America. It is the largest extant member of its family, with males averaging 43โ45 kg and females 36โ38.5 kg. #Wolf #Nature #love #animals #save #saveearth #animal_pocket - @_animal_pocket_ on Instagram
- Animal Photography
- Future shop
- Exiles
- This Coyote lives in my back yard in the center of town. 10/10 would NOT pet!!
- Saint martin vesubie
- The Wolf
- Animals
- Coyotes
- black wolves
- Animals
- Avery Hudson
- The Alpha
- Art inspo
Rate it 1-10! Who else loves these beautiful animals? Follow ๐@wildfriendglobe for daily updates ๐ . Photo by @ofwolvesanddogs . . . . #livewithwolves#worldofwolves#wolves#wolf#wolfdog#realwolfdog#wolfhybrid#whitewolf#dogsofinstagram#dog#canine#instawolf#wolfdogsofinstagram#doglover#nature#animals#animalcuteanimal#awesomeanimals#wolfdogs#instadog#beautiful#lovewolves#wolfpack#woof#arcticwolfdogo #wolfcommunity - @live_with_wolves on Instagram
- The hair stood up in the back of my neck looking at this despite sitting safety on my toilet.
Winter Is Comingโก #boredwolf #wearethewolves #clothingbrand #menswear #streetwear #clothinglabel #wolves #raisedbywolves #designer #wolf #wolfpack #wolfie #lonewolf #howl #80saesthetic - @theboredwolf on Instagram
- Wolf World
No act of kindness no matter how small is ever wasted. ~Aesop Photo by WCC Curator Rebecca Bose #wolfconservationcenter #nikai #alawa #wolves #wolfpack #wolfpack๐บ #kind #bekind #kindness #kindnessmatters #aesop #siblings - @wolfconservationcenter on Instagram
- Hello
- Angry animals
- @heathertucker823 on Instagram
- wolf street
- AniMalS
- ART
- Animal Kingdom
- Lobo
- Spectacular Animals!
- This absolute unit.
- Dogs and Wolves
- Wolf World
- Russian Caucasian dogs
- Animals
- Canada Wildlife
- Wolf images
- Beautiful wolves
It looks like cooler weather is here to stay! Theres still time to come in and enjoy our cozy atmosphere and beautiful fall colors! โ .โ .โ .โ #wisconsinsupperclub #supperclub #wisconsin #bestofmadison #cozy #autumn #fallcolors #oldfashions #ishnala #mirrorlake - @ishnalasupperclub on Instagram
- Blursed wolves [original photo]
- Dog varieties
- Animal Fashion
- Alaskan malamutes and Wolves
- Of Wolf and Man
- tatto viking
- Game of Thrones
- Wolf
Isle Royale wolves are raising puppies, hunting moose, and there are even rumors of a mystery wolf. Researchers report The wolf situation on Isle Royale remains dynamic... See link in bio for the full story #upnorth #minnesota #isleroyalenps #isleroyale #wolves #wolfpups photo via @isleroyalenps #lakesuperior #queticosuperior - @queticosuperior on Instagram
- adorable animals
- Home
- Bars
- Malinois dog
- American Eskimo
- Wolves
- Wolfs
- CARL BRENDERS
- A wolf made entirely of pipe cleaners
@lvzoo is mourning the loss of Mexican gray wolf Beta, who died at the age of 13-and-a-half. . He was under very specific veterinary care for more than two years due to chronic ailments associated with his advanced age. . Learn more at buckscountyherald.com about Beta and what his passing means for his pack. . #LehighValleyZoo #beta #wolfpack ๐บ - @buckscountyherald on Instagram
- Animals, Wild, Wolves
- Apex Tactical Resources Inc
- All Animals
- Beautiful wolves
- Wolf/dog
- Wolf Photos
- Tiny bunny
Entre les annรฉes 1920 et les annรฉes 1990, le parc naturel de Yellowstone na pas vu le loup... Ce qui a eu pour consรฉquence une multiplication du nombre de wapitis, responsables de la dรฉgradation de la vรฉgรฉtation locale. Mais leur population a nettement diminuรฉ ร partir de 1995, annรฉe durant laquelle 41 loups ont รฉtรฉ rรฉintroduits dans le parc. Depuis la flore est redevenue luxuriante, permettant ร bon nombre danimaux de se nourrir et de sabriter. Autrement dit : le prรฉdateur est devenu protecteur. . ยซ Le retour des loups, une chance pour le parc de Yellowstone ยป, un documentaire ร voir en vous rendant sur @artefr (il vous suffira de suivre le lien sous notre photo de profil) ๐ธ . #Yellowstone #Nature #WildLife #ARTEdocu - @artefr on Instagram
Metti like โค๐ฌ๐ @prilaga #girls #sun #dog #vsco #l4l #swag #f4f #sunset #fitness #life #photo #style #hair #party #sky #followforfollow #nofilter #follow4follow #TFLers #vscocam #beach #prilaga #amazing #music #beauty #bestoftheday #pretty #cool #lol - @lupo_italy on Instagram
- Que bottle
- Tribal wolf
- Animals
- Wolf/dog
- dogs
- Curiositร
- 10 interesting facts about grey wolves ๐บ
- wolf & husky
- 2 serious and 1 laughing wolves meme template
Black & White Wolf edit with.. swipe right to see original! ๐๐๐ผ - @cjm_photography on Instagram
- Arctic Wolf
- Animals
- Wolf hybrid puppies
- Animals
- Its mix of 3 types
- The grey wolf is here to take your mind off things
- animals ; wolves.
- wolf hybrid
- Animals
- Illustrations & Posters
- Irish Celtic tattoos
- [Days gone] [Screenshot] This wolf got what he was hunting for! I never knew their fur stayed bloody after eating, amazing detail!
- Eerie CampFire Stories
- Animaux
- Traditional shark tattoo
- Angry Wolf
- Wolf canvas
- Big Wolf
Happy fathers day all!! Over the years we have had some great fathers at the preserve. #lakotawolfpreserve - @lakotawolfpreserve on Instagram
- Tiny bunny
- Snarling wolf
- Colorado Springs Attractions
- Beautiful Wolves
- Animals !
- Doggies and other cuties!!!!
- Wolf Pup
- Cute doggies
- Jon Snow
- Beautiful animals
- Albus Severus Potter
- Wolves In Love
- Black Light Special
- Animals
- Animals in the snow
- All animals
- ๐ฅ Gray Wolf with Pup
- Adventure
- Watercolor wolf
- ๐ฅ Wolf chewing on a moose bone
The Arabian wolf is a subspecies of grey wolf which lives on the Arabian peninsula. #wolf #wolfmoon #wolvesofinstagram #wolves #worldofwolves #canine #animalrights #endangeredspecies #endangered #endangeredanimals #wolfpack #wolvespack #wolfpuppy #wolfdog #realwolf #greywolf #graywolf #savethewolves #wolfrescue #wolfconservationcenter #wolfconservation #savewolves #wolflover #lovewolves #lovewolf #lonewolf #packwolves - @the._.daily._.wolf on Instagram
- Black
- Creatures
- Animal Blankets
- Kurt
- Wolfs
- ๐ฅ wolf in Finland
- Animal
- wolf silhouette
- Wolf
- Beautiful Wolves
- wallpaper lobos
Pretty girl ๐ . PC @bulflowers - @northernlightswolfcentre on Instagram
- Wolves In Love
- Darwin { Evolution }
- Child Tattoos
- Everyone here complaining about Jon and Ghost, but what happened to Nymeria and her pack?
- Animaux sauvages
- Alpha Wolf
- Colorado Tourism
- I got knighted into the pack yesterday. Naโvi is an 8 year old Timber Wolf who loves his belly rubbed.
- Animals
- Japanese pheonix tattoo
- Wolf
- Animals in b/w
๐ฎ๐น I lupi vanno salvati ๐บ โข ๐ฌ๐ง Save the wolves ๐บ ๐พ ๐พ ๐พ ๐ฒ๐ฒ๐ฒ Wanna see your Wolf on my page? DM for collab ๐บ ๐ฒ๐ฒ๐ฒ ๐พ ๐พ ๐พ โข Go follow โข 1) @_amira_thewolfdog ๐บ 2) @shaka_kaya_czechwolfdogs ๐บ 3) @hippie_saarloos ๐บ 4) @kraken_the_wolfdog ๐บ 5) @greywind.wolfdog ๐บ 6) @nymeria.saarlooswolfdog ๐บ 7) @baltic_the_wolfdog ๐บ 8) @lo_scatto_rubato ๐บ 9) @ilupidellealpi ๐บ 10) @shanti.wolfdog ๐พ โข TAG โข #animals #animal #pet #dog #cat #dogs #cats #photooftheday #cute #pets #instagood #animales #๐บ #love #nature #animallovers #pets_of_instagram #petstagram #petsagram #wolf #wolves #wolfpack #wolfsoul #lonewolf๐บ #wolfhowl #greywolf #wolffootprint๐พ - @___w_o_l_v_e_s___ on Instagram
- Animal Rights
- Kurt
- animales
- White wolves
- ๐ฅ Minnesota Black Wolf
- Beautiful Wolves of the World
- Animal Reference
๐ฎ๐น I lupi vanno salvati ๐บ โข ๐ฌ๐ง Save the wolves ๐บ ๐พ ๐พ ๐พ ๐ฒ๐ฒ๐ฒ Wanna see your Wolf on my page? DM for collab ๐บ ๐ฒ๐ฒ๐ฒ ๐พ ๐พ ๐พ โข Go follow โข 1) @_amira_thewolfdog ๐บ 2) @shaka_kaya_czechwolfdogs ๐บ 3) @hippie_saarloos ๐บ 4) @kraken_the_wolfdog ๐บ 5) @greywind.wolfdog ๐บ 6) @nymeria.saarlooswolfdog ๐บ 7) @baltic_the_wolfdog ๐บ 8) @lo_scatto_rubato ๐บ 9) @ilupidellealpi ๐บ 10) @shanti.wolfdog ๐พ โข TAG โข #animals #animal #pet #dog #cat #dogs #cats #photooftheday #cute #pets #instagood #animales #๐บ #love #nature #animallovers #pets_of_instagram #petstagram #petsagram #wolf #wolves #wolfpack #wolfsoul #lonewolf๐บ #wolfhowl #greywolf #wolffootprint๐พ - @___w_o_l_v_e_s___ on Instagram
- Are you the ONE ???
The pack is ready ๐ . Do you love WOLVES ๐บ๐ follow @wo.lfking for more ๐ฅ . If you are interested in promoting your product, book or channel . Welcome, just send a Direct Message ๐ . Photographer๐ท : please DM me . Follow : @wo.lfking . . Follow : @lions.of.insta Follow : @tigers.of.insta . #wolf #wolfdog #wolfmix #wolves #wolves๐บ #wolfs #wolflove #wolfdogsofinstagram #wolfpuppy #loups #wolfdogs #worldofwolves #wolfhybrid #wolfspirit #lobos #instawolf #wolfmother #wolfy #wolfies #wolfhybrid #wolflovers #wolfis #wolfe #wolfring #wolfbracelet #wolfnecklace #vikingring #silverring #wolfjewelry - @wo.lfking on Instagram
- Beautiful Wolves of the World
- [inspire] people + animals
- Alaska...Anchorage
- ITAP of a fox on Mt. Rainier
- Kurt
- Black Wolf
- Hand tattoo frau
- Mystic Wolves
- Wolf
- Animals - Wolves
- Balto / Iditarod
- Wolves
- lone wolf
- Wildlife of North America
- Alpha Wolf
- Backgrounds
Lopane, Lobine, Loux, Lobelinne - @filmwoelfe on Instagram
CREDIT: @gortiz1375 ~#photo #photos #pic #pics #picture #pictures #snapshot #art #beautiful #instagood #photooftheday #color #all_shots #exposure #composition #focus #capture #moment #animal #nature #wolf #dog #wild #winter #wildlife #picoftheday #naturelovers #beautiful - @_photography___shoutouts_ on Instagram
- Photos in bedroom
- Black Dog Tattoo
- ๐ฅ The alpha pair of Yellowstones Canyon pack, who were together for 9 years. They were the longest-reigning alpha pair in Yellowstone history, she is 11 and he is 10 in this photo. Wild wolves only live an average of 4-5 years in Yellowstone.
Hope you all are staying safe. This was one of our favorites. Timber wolf Blackstar. #lakotawolfpreserve - @lakotawolfpreserve on Instagram
- aMelody
- Art Stuff
- Predators and Prey | Hasselblad 500CM | C. Zeiss 80MM | Kodak Portra 400
Our face when we realize the weekend is almost over. ๐ - @naturecanada_ on Instagram
- Lisa young
- Animais
- A well made pack
- Follow the . . .
- Animal Friendships
- Wolf images
- Irish Wolfhound Dogs
- canis lupus
- Animals
- Art inspo
Hi, everyone. This is Emily, Becky and Jimโs daughter. Doing another take-over this year for Jimโs birthday ๐๐ I just wanted to wish him a happy birthday, and ask for you all to flood the comments and the Lakota Facebook page with birthday wishes. I said this last year, but thereโs really no better way to put it: he deserves all of the recognition and well wishes in the world for everything he does! He is an unbelievably hardworking business owner who never, ever stops. Heโs the most caring and protective dad to all of his animals (and me!), a loving husband to my mom, and a truly all-around good guy. Weโre all so lucky to have him, and the preserve just wouldnโt be what it is today without him. Thank you for everything you do, Jim. We love you! - @lakotawolfpreserve on Instagram
- ๐ฅ The critically endangered Red Wolf, one of the rarest canids on the planet with less than 60 wild individuals ๐ฅ
- Wolf Photos
- The Wolf
- animal template
- horse silhouette
- best cinematography
- guard dog
Iโm in love with this black one ๐ค๐บ rate 1/10 โ๏ธ - FOLLOW US @wolf_kg1 โค๏ธ๐บ . By ๐ธ @ DOUBLE TAP IF YOU LIKE ITโ๏ธ๐บ . . #wolves #wolf #wolfdog #wolvesofinstagram #wolflovers #wolfpack #animals #wolfdogsofinstagram #wolfdogs #wolvesup #protectwolves #instawolf #wolfhybrid #worldofwolves #wolfstagram #lupi #wolflover #wolfgang #nativeamerican #avellino #lovewolves #forzalupi #love #wolveslovers #finoallafine #centopercento #maisola #forzaavellino #wolfmillionaire #bhfyp - @wolf_kg1 on Instagram
- Chest charles anttoine
- Wolf Photos
LTL WOLF T- SHIRT available now on LoveTrustLoyalty.com #LoveTrustLoyalty.com #BeGreatDoGreat - @ltlheadquarters on Instagram
#wolf #wolves #greywolf #greywolves #instawolf #wolvesofinstagram #justwolves #rosamondgiffordzoo #wolflovers #ilovewolves #howl #wolfpack #wolfpack๐บ #alpha #alphawolf #wolvesofig #wolf_lovers #lupo #lobo #lobos #loup #canislupus - @sammiesakranphotography on Instagram
. -_-_-_-_-_-_-_-_-_-_-_-_-_-_- ๐จ๐๐๐๐ ๐๐ ๐ฅ๐ @twilight_taylorlautner ๐ญ๐จ๐๐๐ฒโ๐ฌ ๐ญ๐ก๐๐ฆ๐: Day 25. ๐๐จ๐ฅ๐ฅ๐จ๐ฐ๐๐ซ๐ฌ ๐๐จ๐ฎ๐ง๐ญ: 678 -_-_-_-_-_-_-_-_-_-_-_-_-_-_- ๐๐๐๐ฅ๐๐๐ ๐๐๐๐ ๐ฃ๐๐๐ฅ๐๐ ๐ ||๐๐๐ข๐ญ๐๐ ๐๐ฒ: none ||๐ข๐ง๐ฌ๐ฉ๐ข๐ซ๐๐ ๐๐ฒ: none ||๐๐ข๐ฅ๐ญ๐๐ซ ๐๐ฒ: none -_-_-_-_-_-_-_-_-_-_-_-_-_-_- ๐๐ ๐๐๐ ๐จ ๐๐ @twilight_taylorlautner ๐๐ช ๐๐ ๐๐ฃ๐ ๐๐๐จ๐๐ช๐ค ๐ ๐ก๐๐ -_-_-_-_-_-_-_-_-_-_-_-_-_-_- ๐ญ๐๐ ๐ฌ #twilight #twilightsaga #twilightedit #twilightedits #twilightfan #jacobblack #edwardcullen #bellaswan #bellacullen #taylorlautner #robertpattinson #kristenstewart #movie #book #reading #love #newmoon #eclipse #breakingdawnpart1 #breakingdawnpart2 #breakingdawn #vampires #werewolves #challenge #ilovetwilight #twilightforever #bellward #forever #jakella - @twilight_taylorlautner on Instagram
Likeย โค / Comment ๐จ / Save ๐ท / tag โ & share โช with yout friends Follow usย ๐ @wolf_lovers_7 โ ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ๐ย @instawolf14 โ ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ย ๐ธ: DM ๐ฉ For credit & poromtion ๐ & inquiries โ #wolflover #graywolf #howling #wolfhowling #tshritdesiner #wolf๐บ #wolfstar #wolfmix #wolfdogmix #wolfpuppyย #tshirtwolf #wolflove #tshirts #fashion #wolflovers #๐บย #cutewolf #wolfofinstagram #lovelywolf #wolfspirit #wolfcommunity #wolfpackย #savethewolfย #wolfoftheday #tshirtdesigne #animal #animalslover #wolfart #wolfartwork #wolf_lovers_7 - @wolf_lovers_7 on Instagram
- Top p
- Wolf
- Animals *Protect Our Wolves*
- Birds
- Of Wolf and Man
- ใ Viking aesthetic ใ
- Wolf photography
- Tattoos lobo
- animal pics
- Wolf Love
- wolf street
- Albino Animals
- Lakota Wolf Preserve
#ArchivoMongabay En el norte de #Mรฉxico, el lobo gris mexicano ha comenzado a encontrar un hogar. Con su regreso, cientรญficos esperan que tambiรฉn se inicie una recuperaciรณn de los ecosistemas. El muro en la frontera con Estados Unidos amenaza proyecto. Conoce mรกs en ๐ โบ es.mongabay.com Crรฉdito โบWolf Conservation Center - @mongabaylatam on Instagram
- ITAP. Wolves at Parc Omega. Quebec, Canada. Shot with Panasonic Lumix 100-300mm [OC] [2320x1856]
- animals ; wolves.
- ๐ฅ Gray wolf pack looking very serious; Alaska
- You guys are in for a treat, I have dozens of these of my medieval/metal me 10 years ago
- Book Location: Tr
- Animals
- Coolest pic of Wolf Dad and his boys doing their thing
- Save The Planet
- Minnesota, USA: Black Timber Wolf
- ะะฒััั
- Wolf images
- Expensive dogs
- Around Here
- Horse
- **Save Our Earth!
Had an exciting guest today, a wolf hybrid came to visit the ranch! - @ojk9coach on Instagram
- Animals
- Colorblind
- Wolf Dominance
Amazing photo taken by @bradnoblewons ๐๐ผ Trail camera photography is all about having a camera in the right place at the right time! โ โขโ โขโ โขโ #trailcamera #trailcam #trailcampics #trailcamology #cameratrap #canada #nature #natgeo #wildlife #photography #wildlifephotography #igscwildlife #canadaprowildlife #wildlife_perfection #wildlife_seekers #wildlifeaddicts #canadiangeographic #discover_wildlife #imagesofcanada #nature_perfection #wildlifeplanet #canadiancreatives #borealforest #explorecanada #outdoors #fromhereandaway #conservation #wolf - @trailcameraphoto on Instagram
- wallpaper lobos
- Tribal wolf tattoo
- Coyote Mounts
- Twilight Wolf Pack