Anna Blackburne (baptised Anne Blackburne; 1726 – 30 December 1793) was an English botanist and collector who assembled an extensive collection of natural history specimens and corresponded with several notable naturalists of her era. Blackburne was born at Orford Hall, Orford, Warrington, Lancashire, into a family of landowners and merchants. After her mother's death, she lived at Orford with her father John Blackburne, who was known for his interest in botany and his hothouses for exotic plants. John Blackburne also had an extensive library where Anne probably studied botany; she later taught herself Latin so she could read the Systema Naturae of Carl Linnaeus. She developed a natural history museum where she collected insects, shells, minerals and birds. She regularly met with the naturalist Johann Reinhold Forster while he was teaching at Warrington Academy. Forster instructed her in entomology and helped with her insect collection.

Blackburne corresponded with other naturalists including Linnaeus, to whom she sent a box of birds and insects. Her brother Ashton, who lived in New York, sent her specimens of North American birds. The Welsh naturalist Thomas Pennant studied these bird specimens and included them in his book Arctic Zoology. After her father's death, Blackburne and her museum moved to nearby Fairfield Hall. When she died in 1793, her nephew John Blackburne inherited the collection. Several species are named after Blackburne, including the beetle Geotrupes blackburnii, the Blackburnian warbler and the flowering plant Blackburnia pinnata, now called Zanthoxylum pinnatum.

Anna Blackburne was born in 1726 at Orford Hall, Warrington to John Blackburne (1693–1786) and Catherine Ashton (or Katharine Assheton; 1701–1740), as the fourth or fifth of nine children.^{[3][4][5][lower-alpha 1][lower-alpha 2]} Her maternal grandfather was William Assheton, Rector of Prestwich, and the collector Ashton Lever, who established the Leverian Museum, was a cousin on her mother's side.^[11][12] She was baptised as "Anne" on 3 January 1726,^{[lower-alpha 3]} but was usually known as "Anna".^[3][4][14] Her family were landowners who had lived at Orford Hall since 1638.^[15] They also owned merchant ships, were involved in trade with Russia, and produced salt in Cheshire that was then exported from Salthouse Dock in Liverpool.^[16] John Blackburne was interested in botany and had a large collection of plants in his garden. In his hothouses, he grew exotic plants including pineapples and cotton. Some of this cotton was noted to have been made into a muslin dress for his daughter.^[3][17] Little is known about Anna's early education,^[6] but she may have used the natural history books in her father's library to study botany during her childhood.^[18] In the years following her mother's 1740 death, Anna's surviving siblings left Orford Hall until eventually only Anna, who became the mistress of the manor, and her father remained.^[6] Her brother John was a businessman who served as mayor of Liverpool in 1760–61 and was involved in the slave trade before 1758;^[19] her brother Ashton lived in New York,^[3] from where he sent bird specimens to his sister.^[20] Anna referred to herself as "Mrs. Blackburne" although she never married; the title "Mrs." was customarily used also by unmarried ladies of the 18th century.^[6]

Blackburne was keenly interested in natural history, and her biographer V. P. Wystrach described her as a "patroness of natural history".^[21] Natural history as a field of study was not precisely defined but certainly included the study of natural objects and organisms.^[22] Blackburne did not contribute to botany and ornithology as an author in her own right, but she was widely known for the extensive and influential collection that she assembled, and she has been described as a "botanist".^[3][21] She was in contact with several well-known naturalists, and some of them visited her and her father at Orford Hall.^[4][23] She learned Latin so she could study the Systema Naturae of Linnaeus.^[24][25] Occasionally, Blackburne visited London and Oxford;^[26] on one such visit to the botanical garden at Oxford, she debated with the gardeners about the geranium and surprised the bystanders with the extent of her botanical knowledge.^[27] She collected natural history specimens including insects, shells, minerals and birds.^[4] In the early years of her collection, she obtained most of her specimens from her widely travelled family members; she later bartered and exchanged specimens with other collectors.^[28][29]

Anna Blackburne assembled a museum with an extensive collection of natural history specimens, comparable to the Leverian collection of her cousin Ashton Lever.^[3][56] The museum included a herbarium of preserved plant specimens, a collection of 470 birds and one bat preserved by taxidermy, specimens of insects, corals and shells, as well as fossils, ores, and minerals.^[10][29] She probably also commissioned drawings of her specimens, and around 1768 the illustrator James Bolton made several watercolours and gouaches from objects in her collection.^[57][58] After her father's 1786 death, Blackburne moved in 1787 from Orford Hall to Fairfield Hall, which was a new home built for her with a room designed to house her collections.^[59] The room was 15 yards (14 m) long, as wide as the entire front of the house.^[29][60] She also had plans for a botanical garden, but was unable to carry these out due to health issues.^[6] She died on 30 December 1793, and was buried in the churchyard of St Oswald's Church, Winwick.^[6] In her will, she bequeathed more than £12,000 (equivalent to £1,500,000 in 2021) to her family and to charity.^[3][61] Her museum was inherited by her nephew John Blackburne, the son of her brother Thomas, and John moved selected parts of the collection to his manor at Hale Hall.^[60][62][63] The Blackburne family homes at Orford, Fairfield and Hale Hall were all demolished in the 20th century, and the eventual fate of the collection is unknown; it was probably dispersed at auctions.^[64] Some plant specimens attributed to Blackburne's collection are now in the herbarium of Liverpool Museum, and Bolton's watercolours are in the collection of the Yale Center for British Art.^[57][65]

A crater on Venus has been named "Blackburne" in her honour since 1994.^[66] The Blackburne crater is situated at 11.0°N, 183.9°E and has a diameter of 30.1 km.^[67]