| 2023-06-01 | Sparrowhawk (female) | | bird | | |
| 2023-06-05 | White-tailed Eagle (Aquila chrysaetos) | | bird | Observed through garden. | |
| 2023-06-06 | White-tailed Eagle | | bird | | |
| 2023-06-06 | Map-winged Swift (Moths) | | moth | new for year | |
| 2023-06-06 | Elephant Hawk-moth (Moths) | | moth | | |
| 2023-06-06 | Poplar Hawk-moth (Moths) | | moth | | |
| 2023-06-06 | Clouded-bordered Brindle (Moths) | | moth | | |
| 2023-06-06 | Flame Shoulder (Moths) | | moth | | |
| 2023-06-06 | Campion (Moths) | | moth | | |
| 2023-06-06 | Drinker (Moths) | | moth | | |
| 2023-06-06 | Broom (Moths) | | moth | | |
| 2023-06-06 | Bright-line Brown-eye (Moths) | | moth | | |
| 2023-06-06 | Dusky Brocade (Moths) | | moth | | |
| 2023-06-06 | Shears (Moths) | | moth | | |
| 2023-06-06 | Knotgrass (Moths) | | moth | | |
| 2023-06-06 | Buff Tip (Moths) | | moth | | |
| 2023-06-06 | _Anania fuscalis_ (Moths) | | moth | | |
| 2023-06-06 | Northern Marsh Orchid | 4 | plant | on our drive! | |
| 2023-06-06 | Early Purple Orchid | 120 | plant | a fantastic array at a new location on Ben Hogh | |
| 2023-06-06 | Whinchat | | bird | reported from Arinagour | |
| 2023-06-07 | Fox | | moth | New for year sighting of moths. | Uncommon |
| 2023-06-07 | Grey Scalloped Bar | | moth | New for year sighting of moths. | Uncommon |
| 2023-06-07 | White Ermine | | moth | New for year sighting of moths. | Uncommon |
| 2023-06-07 | Buff Ermine | | moth | New for year sighting of moths. | Uncommon |
| 2023-06-07 | Heart & Dart | | moth | New for year sighting of moths. | Uncommon |
| 2023-06-07 | Risso’s Dolphins | | mammal | Reported off New Pier. | Notable |
| 2023-06-10 | Red-breasted Merganser | | bird | | |
| 2023-06-10 | Sanderling | | bird | | |
| 2023-06-10 | Dunlin | 7 | bird | | |
| 2023-06-10 | Snipe | | bird | drumming | |
| 2023-06-10 | Black-headed Gull | | bird | | |
| 2023-06-10 | Little Tern | | bird | | |
| 2023-06-10 | Red Admiral | | insect | a significant arrival today | Significant Arrival |
| 2023-06-10 | Brown Silver-line moth | | moth | | |
| 2023-06-10 | Early Purple Orchid | | plant | | Early bloom |
| 2023-06-10 | Pyramidal Orchid | | plant | | |
| 2023-06-10 | Sea Radish | | plant | | |
| 2023-06-11 | White-tailed Eagle | | bird | | |
| 2023-06-11 | Hen Harrier (male) | | bird | | |
| 2023-06-11 | Chimney Sweeper (a new moth for Coll!) | | moth | New moth sighting for Coll. | Uncommon |
| 2023-06-11 | Tall Fescue and Hairy Sedge | | plant | Both doing well at only known location on Coll. | |
| 2023-06-11 | Common Dolphin | | mammal | c20 off The Meall | |
| 2023-06-12 | Red-throated Diver | | bird | | |
| 2023-06-12 | Hen Harrier | | bird | | |
| 2023-06-12 | Corncrake (good views of calling birds) | | bird | | |
| 2023-06-12 | Black-headed Gull (x2) | 2 | bird | | |
| 2023-06-12 | Arctic Skua | | bird | | |
| 2023-06-12 | Spotted Flycatcher (an uncommon migrant here on Coll) | | bird | | Uncommon |
| 2023-06-12 | Large Heath butterfly | | insect | | |
| 2023-06-12 | Dark Green Fritillary butterfly | | insect | | |
| 2023-06-12 | Purple Bar moth | | moth | | |
| 2023-06-12 | Sea Bindweed (at only known station on Coll) | | plant | At only known station on Coll | |
| 2023-06-13 | Red-throated Diver | | bird | | |
| 2023-06-13 | Arctic Skua | | bird | | |
| 2023-06-13 | Great Skua | | bird | | |
| 2023-06-13 | Manx Shearwater (a colossal raft of birds west of Coll) | | bird | Massive flock west of Coll. | Uncommon |
| 2023-06-13 | Common Dolphin | | mammal | | |
| 2023-06-13 | Four-spotted Chaser | | insect | | |
| 2023-06-13 | Magpie moth (a mass emergence today) | | moth | Mass emergence event. | Notable |
| 2023-06-13 | Six-spot Burnet moth | | moth | | |
| 2023-06-13 | Clouded Border moth | | moth | | |
| 2023-06-13 | Pale Butterwort | | plant | | |
| 2023-06-13 | Oblong-leaved Sundew | | plant | | |
| 2023-06-13 | Royal Fern | | plant | | |
| 2023-06-14 | Woodpigeon | | bird | | |
| 2023-06-14 | Moths: new for year | | moth | New for year: True Lover’s Knot, Dark Arches, Northern Rustic, _Eana penziana_ | New for year |
| 2023-06-14 | Frog Orchid | | plant | | First of the year |
| 2023-06-14 | Lesser Butterfly Orchid | | plant | | |
| 2023-06-14 | Fragrant Orchid | | plant | | First of the year |
| 2023-06-14 | Marsh St John’s Wort | | plant | | |
| 2023-06-14 | Pipewort | | plant | | |
| 2023-06-14 | Water Lobelia | | plant | | |
| 2023-06-14 | Lesser Marshwort | | plant | | |
| 2023-06-15 | Great Northern Diver (Alkionyx cinerea) | 4 | bird | Displaying and calling | |
| 2023-06-15 | Arctic Skua (Stercorarius arctica) | | bird | | |
| 2023-06-15 | Great Skua (Stercorarius skutilensis) | | bird | | |
| 2023-06-15 | Fulmar (Fulmarus glacialis) | | bird | | |
| 2023-06-15 | Hen Harrier (Circus cyaneus) | | bird | | |
| 2023-06-15 | Harbour Porpoise (Phocoena phocoena) | 4 | mammal | Seen from New Pier | |
| 2023-06-15 | Meadow Brown (Maniola smyrna) | | insect | First of the year | Uncommon |
| 2023-06-15 | Yellow Shell moth (Caloptilia xanthopyga) | | moth | In abundance in the machair | |
| 2023-06-15 | Northern Colletes bee (Colletes bombus) | | invertebrate | | |
| 2023-06-22 | Hen Harrier (male and female birds) | | bird | | |
| 2023-06-22 | Twite | 2 | bird | | |
| 2023-06-22 | Greenfinch | 14 | bird | Three family groups together | |
| 2023-06-22 | Marsh Fritillary | | insect | New butterfly for Coll | New |
| 2023-06-22 | Silver Hook | | moth | New moth for Coll | New |
| 2023-06-22 | Wood Tiger moth | | moth | At a new location for Coll | New |
| 2023-06-22 | Adder’s Tongue Fern | | plant | A nice little colony among Bracken | |
| 2023-06-22 | Heath Violet | | plant | Newly discovered site for Coll | New |
| 2023-06-22 | Lesser Water Plantain | | plant | Flowering | |
| 2023-06-22 | Marsh Arrowgrass | | plant | Flowering | |
| 2023-06-24 | Hen Harrier (female) | | bird | | |
| 2023-06-24 | Kestrel | | bird | | |
| 2023-06-24 | Woodpigeon | | bird | | |
| 2023-06-24 | Common Wave moth | | moth | | |
| 2023-06-24 | Painted Lady (new for year) | | butterfly | | First of year |
| 2023-06-26 | Red-throated Diver | | bird | | |
| 2023-06-26 | White-tailed Eagle | | bird | | |
| 2023-06-26 | Arctic Skua | | bird | | |
| 2023-06-26 | Fulmar (an outlier of x3 nesting birds away from the usual colony) | | bird | Unusual nesting behavior | Uncommon |
| 2023-06-26 | Common Wave moth | | moth | | |
| 2023-06-26 | Woodpigeon (x2) | 2 | bird | | |
| 2023-06-26 | Golden Eagle reported | | bird | | Reported only - not observed. |
| 2023-06-27 | Hen Harrier (both males and females regularly being observed now - evidence of nestlings) | | bird | | Regular sightings, evidence of nesting |
| 2023-06-27 | Great Skua | | bird | Just a single bird over the cottage - still in very short supply this year | Short supply |
| 2023-06-27 | Woodpigeon | | bird | a pair - be still my trembling heart! | |
| 2023-06-27 | Spotted Flycatcher | | bird | a single bird has been in the same area on and off for several weeks now | Long-term presence |
| 2023-06-27 | Silver Ground Carpet | | moth | a delightful moth | |
| 2023-06-29 | Bonxie (in short supply this year as a result of Bird Flu) | | bird | | Uncommon due to Bird Flu |
